Ahead of the first clay Masters event of the year getting under way on Sunday, we look at the main issues on the ATP Tour
How fit is Murray?
After withdrawing from Miami with a tear in his elbow, and having been laid low by flu and shingles already this year, Andy Murray has endured a pretty rough start to 2017.
There has been a suggestion that these fitness issues are due to the monumental effort Murray put into chasing down the world No 1 ranking last year, coupled with a particularly brutal off-season training camp.
But whatever the reasons, Murray knows he needs to get back playing soon. He is not in immediate danger of losing the No 1 ranking, but to stand any chance at the French Open he'll need to get plenty of practice on the clay at Monte Carlo, Madrid and Rome.
It is hard to know what shape Murray will be in for Monte Carlo next week. He has been training at Patrick Mouratoglou's academy in the south of France and played an exhibition match against Roger Federer on Monday where he looked in reasonable health, though he admits he still can't serve at the pace he would like to.
"I'm hoping, if I keep progressing as I have with the elbow, to play Monte Carlo," Murray said on Wednesday. "If not, then I just need to stay patient and I'll try the following week. I'm getting there, I just have to go slowly."
Jamie Delgado and the rest of Murray's team will doubtless ensure their man only competes in Monte Carlo if he is ready, and they must balance making sure he gets onto the clay as soon as possible without risking his fitness longer-term with bigger prizes on the horizon.
Who knows, perhaps Murray will benefit from some time out. It has seemed to work quite well for Federer.
Is Djokovic ready to kick-start season?
Novak Djokovic spoke of being "pumped up to do well in other tournaments" after helping Serbia dismantle Spain in the Davis Cup quarter-final last week.
The world No 2 became the only current top-10 player to compete in the competition this year, with his singles rubber victory over Albert Ramos Vinolas getting Serbia off to a winning start against a Spain outfit lacking their big guns.
It was the 12-time grand slam champion's first match back after missing the Miami Open with an elbow injury. Djokovic came through unscathed and reflected on the "positive energy" the tie in Belgrade has given him.
Pleasure, determination, community, self belief, passion, trust.. OMG guys you are amazing!! Keep sending your #Sportin1Word! Love it ������— Novak Djokovic (@DjokerNole) April 8, 2017
Despite winning the Qatar Open in the first event of the year, Djokovic has not gone past the quarter-finals in any of the tournaments he's played since.
Not only is Djokovic in need of kick-starting his season, the Serb returns to Monte Carlo with the scars of last year's early exit at the forefront of his mind.
Jiri Vesely stunned Djokovic in the second round for only his second loss of the season and his earliest tournament defeat in three years.
Back then an early exit was merely a smudge on his copybook as he went on to land the Madrid title and the major he craved at Roland Garros. Another early departure this time round would be far more damaging for his chances of winning the French Open.
Can Nadal fill the void left by Federer?
Under normal circumstances, Rafael Nadal's renaissance over the last few months would be the biggest story in tennis. Nadal has, after all, recovered from an injury-ravaged couple of years to reach three finals, including at the Australian Open, and sit second in the Race to London rankings.
The problem is that Nadal's achievements have been trumped by the even greater rebirth of his long-time rival Roger Federer. The all-conquering Federer has beaten Nadal three times already in 2017, and looks finally to have worked out a way to consistently get the better of a player who for so long was his bête noire.
Federer though will be absent in Monte Carlo, as he will be from all events until the French Open, leaving Nadal primed to pick up some titles in the coming weeks. The Spaniard is the greatest clay-courter of all time, and has won the Monte Carlo Masters on nine occasions, including last year. He also won 46 consecutive matches in the Principality between 2005 and 2013, the longest streak by any male or female player at a single tournament in the history of the sport.
In short, Nadal should go into next week full of confidence. And if he can dominate the clay-court swing then he could overtake Federer in the Race rankings by the time Wimbledon starts and have a real shot at finishing the year as the world No 1.
Will fatherhood inspire Tsonga?
As it turns out, France didn't need the bludgeoning might of their No 1 Jo-Wilfried Tsonga for the Davis Cup tie against Great Britain last week.
The 31-year-old has been on a self-imposed break since becoming a dad for the first time in late March. The world No 10 opted to sit out the second part of the 'Sunshine Swing' in Miami and then the Davis Cup weekend to take in every moment of the first days of fatherhood.
"Having a child changes your priorities," Tsonga said when he announced news of the pregnancy back in early November. "I am convinced, for me, it will be something very positive and give me even more motivation."
Des étoiles plein les yeux, je vous annonce la naissance de notre fils ! ���� pic.twitter.com/hM5XZrFYXY— Jo-Wilfried Tsonga (@tsonga7) March 24, 2017
The new-dad effect has certainly worked wonders for Novak Djokovic and Andy Murray in recent years. Both players enjoyed an annus mirabilis following the arrivals of their first born.
Tsonga had been in fine fettle before taking his extended paternity break. Back-to-back victories in Rotterdam and Marseille in February saw him leap four places in the rankings to world No 7. It was his highest position since May 2016.
The Frenchman has also enjoyed solid runs in Monte Carlo in recent years. Last year he saw off Lucas Pouille and then Federer en route to the last four only to suffer defeat to compatriot Gael Monfils.
A similar run back in 2013 saw him sweep aside Jurgen Melzer and Stan Wawrinka only to come up against the King of Clay Nadal for a place in the final. Could this be the year he goes all the way as he looks to win a third Masters title and a first on clay?
Will Wawrinka fly under the radar?
He's won a grand slam in each of the last three years, and is No 3 in the world, but Stan Wawrinka is still rarely tipped to win the biggest events.
Part of that is down to his inconsistency, which can see him blitz his way to a major title one tournament and exit a 500 event in the first round the next. Wawrinka's record generally at the Masters events is mixed, with just one such title to his name in his career, in Monte Carlo three years ago. When asked after winning the 2016 US Open how he could have won three grand slams, but just one Masters, the Swiss laughed and replied: "I don’t care. I’m happy."
So far this year Wawrinka has reached the Australian Open semis and Indian Wells final, and he should benefit from the switch to clay - a surface on which he has won both a grand slam and a Masters.
In theory then Wawrinka should be well placed to win his second Monte Carlo title - especially given that many of his rivals have been carrying injuries - but at the same time it would be no surprise to see him bomb out to a qualifier early on.
Is Zverev on verge of a breakthrough?
But for a rejuvenated and refocused Nick Kyrgios, Alexander Zverev would have booked a first Masters semi-final appearance of his career in Miami.
The 19-year-old had earlier come from a set down to stun top seed Wawrinka and steered his way through a three-setter against John Isner which comprised three tie-breaks.
Kyrgios proved a thorn in the teenager's side throughout the Sunshine Swing as the Australian ended his run in Indian Wells too.
Zverev is coping admirably in the face of being dubbed a 'future No 1' and multiple slam winner by the tennis elite. He added to his St Petersburg title of last November with victory over Richard Gasquet in the final of Montpellier back in February. Now he must transfer that solid hard-court form on to the red stuff in his own backyard.
The German, who resides in Monte Carlo, has decent pedigree on clay with his strongest outing yet a run to the final in Nice last May in his final warm-up before Roland Garros.
There was no disgrace in his final defeat to Dominic Thiem, a player who he was to come up against again at the French Open where he battled to win the opening set but lost in four.
Zverev's stamina levels and experience are building with every tournament run - the teenager will just be hoping to avoid facing Kyrgios and Thiem anytime soon in the coming weeks. A task that was made easier by the withdrawal of an exhausted Kyrgios from Monte Carlo.
Will Thiem lay down a marker for the clay-court season?
Dominic Thiem is one of those players who you fear might be being tipped as 'one for the future' until he's about 30. The Austrian is still young, at 23, but he needs only to look at the so-called 'lost generation' of Milos Raonic (26), Kei Nishikori (27) and Grigor Dimitrov (25) to see that being endlessly tipped to win a major does not necessarily mean you will do so.
If Thiem is to be a future slam champion, then the French Open looks like his best bet. The clay suits Thiem's baseline game, and provides the best platform for him to unload on that picture-book single-handed backhand.
He was a Roland Garros semi-finalist last-year and will want to lay down a marker for the clay-court season in Monte Carlo, especially given Federer's absence and the various ailments of Djokovic and Murray.
For so long we've heard about Thiem's potential, but the time has come for him to start demonstrating what all the fuss is about on a more regular basis.