0km - Sylvain Chavanel does enough to limit his loses and take the red jersey today. Chapeau for the Quick Step man.
0km - Euskaltel's Igor Anton crosses the line 1:36 down on the winner, Moreno. That's a bad day for the Spaniard, who lost over a minute to his main GC rivals.
0km - Yes, Daniel Moreno (Katusha) takes the stage two seconds ahead of Chris Anker Sorensen (Saxo Bank). The peloton is led over the line another 15 seconds back by Garmin's Dan Martin.
0.5km - Moreno puts in an attack in the closing 500m and he easily opens up a gap - the win will be his.
1km - Wiggins is right up towards the front of the bunch as the chasers pass the Flamme Rouge.
1.5km - But now Chavanel is being distanced. The French national champion is off the back of the bunch - although he has a minute or so to play with over the others in the GC. May be a big ask though.
2km - France's Sylvain Chavanel is in the main group, which would mean he would move into the red jersey tonight. The two leaders have 12 seconds.
3km - Bonnafond can't hold on and he is finally swept up by the peloton. Moreno and Sorensen continue up ahead, although they only have a handful of seconds over the bunch.
4km - But it's not over for Katusha - Daniel Moreno attacks just as the remnants of the break are reeled in. The Spaniard is set to join the two leaders, Sorensen and Bonnafond.
4km - Sorensen continues past the leaders, taking Bonnafond with him. The others can't follow and Vorganov is the first to be caught by the peloton. The other three follow soon after.
5km - Sorensen and Kiserlovski have caught the four leaders under the 5km-to-go banner.
6km - Meanwhile, it looks like Igor Anton has been dropped by this main bunch. The Euskatel rider is clearly having an off day in the fierce heat. Liquigas lay down the hammer and set a hefty pace on the front. Irish fans: both Dan Martin (Garmin) and Nicolas Roche (Ag2R) are there.
7km - That was just a marker by Nibali, to remind his rivals that he's got form. He's pulled back just as there's another attack, this time by Astana's Robert Kiserlovski, who follows a move by Saxo's Chris Anker Sorensen.
7km - ATTACK: Nibali ups the pace and jumps off the front of the peloton. The shutting down is done by Rabobank's Steven Kruijswijk.
8km - Liquigas have come to the front. Defending champion Vincenzo Nibali has Sky's Bradley Wiggins right in his wheel. They have caught Rafal Majka, who has run out of steam after his earlier determined attack.
9km - The gap is 1:17 at the 9km-to-go mark. This is going to be an exciting finish.
10km - Attack from Rafal Majka (Saxo Bank). The Polish rider jumps clear of the peloton and passes the suffering Toribio, who has found his legs again, but still looks to lose a lot of time today.
10km - We will definitely have a new leader tonight: the Lastras group is 5:15 down on the main peloton. The four leaders have 1:30 now, so it's going to be tight.
12km - All the race favourites are on the front of this main bunch - with the exception of Igor Anton. It looks like the Euskaltel rider is struggling a little at the back...
13km - Jose Vicente Toribio is in a world of pain. The Spaniard has hit the wall big time and is pedalling squares. The Andalucia rider had just caught up with the four leaders before sensationally bonking. He's be caught by the peloton, passed and then finish well down today, that's for sure.
13km - The gap is 1:45 as Euskaltel's Gorka Verdugo drops back to pick up some water bottles for his team-mates. Igor Anton will eye a strong finish today, that's for sure.
14km - It's very hot out there - still above 30 degrees. All of the four leaders, with the exception of Bonnafond, have their jerseys open. Weather report for Sierra Nevada
15km - The four leaders are onto the flatter intermediate part of this climb. Rohregger looks to be the danger man. Back on the front of the bunch, it's Vacansoleil who have come forward as well as Quick Step.
17km - The gap is 2:07 for the leading quartet of Rohregger, Bonnafond, Vorganov and Bushe. They have dropped De Kort and Toribio, who ride 15 seconds back, and Bagot, who is now being caught by the peloton.
18km - Red jersey Pablo Lastras has been dropped by the main bunch. He's riding in a small group firther back down the road. Rabobank's Carlos Barredo is there too.
18km - Vladimir Karpets of Katusha is now setting the pace on the front of the peloton, working hard for his team-mate Joaquin Rodriguez.
18km - Andreas Kloden is suffering. The German is right off the back of the peloton. He lost almost 10 minutes yesterday. We can probably expect another withdrawal...
19km - Already, numerous riders are being spat off the back of the peloton, including a whole host of Astana riders. Rabobank and Liquigas are setting a fierce pace on the front.
19km - Thomas Rohregger is setting the pace with the leaders. The Austrian is no longer the virtual red jersey but he's still bent on getting the stage win for Leopard Trek.
20km - The leaders are onto the Cat.1 climb to Sierra Nevada, which has an average gradient of 5.7 percent and rises to well over 2,000m.
22km - As the leaders approach the final climb of the day, the lead is down to 2:55.
26km - The gap is 4:10 now with the final climb to Sierra Nevada looming.
32km - Rabobank have reduced the gap to under five minutes, but it's looking good for the break.
38km - Rabobank have now moved to the front of the peloton to lead the chase. This looks promising - the lead has already dropped to 5:35.
40km - NEWSFLASH: Mark Cavendish has retired from the Vuelta. It's gets worse and worse for HTC in their final Grand Tour before folding. Cav has looked off the boil throughout the race, clearly overheating and out of form.
42km - Koen de Kort consolidates his lead at the top of the king of the mountains competition with maximum points over the summit of the Cat.3 Los Blancares pass. The Skil Shimano rider also took maximum points over the first climb of the day, the Cat.1 Alto de Filabres, so is looking good for the polka dot jersey - provided these men stay out ahead. Thomas Rohregger crossed in second place, and the pair have opened up a small gap over the others.
45km - The lead is down to 6:55 as Katusha come to the front alongside Movistar. Parhaps the Russians eye a win for their man Joaquin Rodriguez today? Who is your tip for victory at the summit of Sierra Nevada? Have your say below...
48km - Frenchman David Moncoutie is off the back of the peloton in search of water. The Cofidis veteran was the last rider to win atop Sierre Nevada, back in the 2009 race. The peloton will attack the climb from the opposite side this year, however.
50km - A reminder of the seven leaders: Guillaume Bonnafond (Ag2R), Matthew Bushe (RadioShack), Yohan Bagot (Cofidis), Thomas Rohregger (Leopard Trek), Eduard Vorganov (Katusha), Jose Vicente Toribio (Andalucia Caja Granada) and Koen De Kort (Skil Shimano). They have 7:20 over the Movistar-led peloton.
53km - The leaders are on to the 6.2km-long Cat.3 climb of Los Blancares.
55km - Denis Menchov was not the only rider to lose out yesterday. While the Russian lost 1:23 over his GC rivals, that was nothing compared to the 10-odd minutes lost by Andreas Kloeden (RadioShack) and Tony Martin (HTC).
60km - The race is LIVE NOW on British Eurosport (Sky 410 / Virgin Media 521) and is also available on your PC via the Eurosport Player: click here to subscribe
65km - Rabobank's Luis Leon Sanchez needs to drop back to see the medical car. Meanwhile, Fabian Cancellara goes to see his Leopard Trek team car with a mechanical problem.
70km - The lead has grown to just over eight minutes. But all ther drama of today's stage is still yet to play out, what with those two decisive climbs coming up.
80km - The leaders pass through the feeding zone with a lead of seven minutes over the peloton.
90km - It's stalemate on the road with the seven leaders maintaining a gap of around 6:30 in this flat middle segment of today's stage. The feeding zone is coming up, then we'll have the Cat.3 Puerto de los Blancares climb, a zippy descent and then the final long climb up to Sierre Nevada.
95km - At the intermediate sprint at Hueneja, it was Rohregger who picked up the maximum four points ahead of Toribio (2) and Bonnafond (1).
100km - Vorganov is back with the leading group, who are now approaching the first intermediate sprint of the day. Rohregger is still the virtual race leader on the road. The gap has slablised at 6:55 but the temperature is up to 35 degrees.
105km - The peloton is back together again after that split. Lucky for Wiggins - that could have been dangerous.
105km - Back with the leaders, Toribio is back after his puncture - but Vorgonav now has a mechanical problem. The escape has 6:25 over the bunch.
110km - There's a split in the peloton and the second group continues some big names: Bradley Wiggins (Sky), Sylvain Chavanel (Quick Step) and Markel Irizar (RadioShack).
120km - The gap is coming down a little now Movistar have taken up the slack. It's 6:35 as the escapees approach the bottom of the descent. Toribio is still 40-odd seconds back - he'll have to wait until the next slight uphill rise until he can rejoin the leaders.
130km - Jose Vincente Toribio picks up a puncture on the descent and needs a wheel change. He's 40 seconds down on his fellow escapees and so has some ground to make up. Back in the bunch, it's the Movistar team of red jersey Pablo Lastras setting the pace.
138km - Order over the summit of the Cat.1 Alto de Filabres: 1. De Kort, 2. Vorganov, 3. Rohregger, 4. Bagot, 5. Bonnafond. That will put the Dutchman De Kort into the virtual polka dot jersey. The gap over the peloton is 7:20.
140km - Many apologies for readers inquiring about the stage graphic. There have been some problems with the official Vuelta feed and graphic and so Eurosport is not running it this year. But we hope to have a stage profile up every day before too long, so bear with us. Enjoy the race.
140km - The seven-man break have a lead of 5:10 as they approach the summit of this first climb.
141km - And finally, Russian Eduard Vorganov (Katusha) is one of the most experienced of the seven leaders, having already ridden in the Vuelta three times. The 28-year-old has no big wins to his name, but he had a particularly active Giro d'Italia in May after breaking clear of the pack on numerous occasions.
142km - Dutchman Koen de Kort, 28, is also riding his debut Vuelta. The Skil Skimano rider's only UCI wins came back in 2004 and 2005 as a junior. France's Yoann Bagot, 23, is in his first year as a professional for Codifis and is riding his first Vuelta. Spaniard Jose Vicente Toribio (Andalucia) is riding his second Vuelta. The 25-year-old's only UCI win came in the Volta a Portugal last month.
143km - Rookie Frenchman Guillaume Bonnafond (Ag2R) is racing his second Vuelta. Aged 24, Bonnafond has no professional wins to his name. American Matthew Bushe (RadioShack) is making his Vuelta debut. The 26-year-old has just one UCI win to his name: the 2011 USA road race championships.
144km - Let's take a look at the leading riders, starting with that man Thomas Rohregger, the virtual red jersey on the road. The Austrian 28-year-old joined Leopard Trek from Milram last winter and is riding his second Vuelta. His only UCI wins came back in 2007 and 2008 at the Osterreich Rundfahrt.
145km - The lead continues to grow: 4:15 at the latest check, but there is still 8km of this climb to go. Rohregger is the virtual red jersey on the road: this morning, the Austrian trailed race leader Pablo Lastras by 3:18 down in 47th place.
148km - The peloton is refusing to panic as the lead grows to 3:50 on this long opening climb. Yesterday, Pablo Lastra's celebration as he crossed the line was as long as it was poignant... Read more about it here: Blazin' Saddles: Lustrous Lastras
150km - The seven-man break now have a lead of 2:42 over the bunch as the temperature drops to 28 degrees.
153km - The riders are onto the Cat.1 Filabres Pass, which is making its Vuelta debut. It's 21km long, 2,040 metres high and has an average gradient of 5 percent.
155km - Those two riders are joined by five more and we have a break of seven hitting the first climb of the day, the Cat.1 Alto de Filabres. The leaders are: Guillaume Bonnafond (Ag2R), Matthew Bushe (RadioShack), Yohan Bagot (Cofidis), Thomas Rohregger (Leopard Trek), Eduard Vorganov (Katusha), Jose Vicente Toribio (Andalucia Caja Granada) and Koen De Kort (Skil Shimano).
160km - It's been a pretty active start to the stage so far. Quick Step have made several attempts to get riders clear, as have Omega Pharma Lotto and HTC. The latter outfit had another terrible day in the saddle yesterday after their sprinter Mark Cavendish suffered on the first hills of the race and needed support from a bunch of team-mates just to make it to the finish. Two riders are currently out ahead of the peloton - details coming up.
165km - It's a clean sweep for Pablo Lastras: not only is the Spanish veteran wearing the red jersey after yesterday's stage win, he's also topping the points and mountains standings. Given he's in red today as the race leader, Sylvain Chavanel, runner-up in stage three, will wear the green jersey and Spain's Markel Irizar will be in polka dots. Vuelta standings and results
168km - One of the big losers yesterday was Russia's Denis Menchov, who lost one minute 23 seconds to his GC rivals on what should not have proved a hard stage for the Geox rider. Report: Menchov slides out of contention
170km - The sun is out at the start in the Andalucian town of Baza. It's not as hot as yesterday, but temperatures are still around 30 degrees. Baza weather report
172km - They're off! This tricky fourth stage of the Vuelta is underway. On the agenda today: two first category climbs and a third category climb. It may be early in the race, but the GC contenders will have nowhere to hide out there today.
11:55 - All 197 remaining riders signed on this morning. Christophe Le Mevel (Garmin) continues despite a hard fall yesterday, as does Antonio Piedra Perez (Andalucia Caja Granada), who also crashed and needed six stitches in his left arm. HTC's Matt Goss is the only rider to withdraw after pulling out with an illness on Sunday.
11:50 - Yesterday, Spanish veteran Pablo Lastras (Movistar) moved into the race lead after soloing to a well-judged win in Totana. Report: Lastras takes win and red jersey
11:45 - Welcome to stage four of the Vuelta a Espana, a hilly 170km ride from Baza to Sierra Nevada which includes two testing climbs each more than 20km long. With the first summit finish of the race coming as early as day four, the main men for the GC should come to the fore today.