Alfa Romeo’s Zhou Guanyu stole the headlines with a session-topping run in Day Two of Bahrain testing, while Mercedes encountered issues during the evening of the test.

It looked for much of the afternoon session that Max Verstappen was going to retain his stranglehold on that P1 spot, but Zhou would upset the Red Bull party by putting his C5 tyres to full use, clocking a 1:31.610 which could not be toppled.

Fernando Alonso continued Aston Martin’s impressive form, just over half a second shy of Verstappen on the same C3 compound, while for Ferrari there was no route into the top five.

At least they made it through the day though, which was not the case for Mercedes as a hydraulics issue cut George Russell’s running short.

Over 600 laps were covered during the opening session on Friday at the Bahrain International Circuit, yet it was a session which ticked on by with very few sticking points.

The extend of the drama was a few flying pieces of bodywork and a dodgy practice race start, so for the teams and drivers, this was a very welcomed four hours of data gathering.

Sergio Perez was behind the wheel of the RB19 for the first time as the Friday action got underway, his 1:33.751 not a P1 time as he focused on race simulations. Kevin Magnussen then just about made it past the first hour at the top of the timesheets, before Carlos Sainz put a stop to that in the Ferrari, clocking a 1:32.486.

Lewis Hamilton was one of those to see some bodywork fly free from his machinery, the W14 needing some time in the garage as Mercedes assessed that damage and also had a close look at the cooling louvers. The seven-time champ wants title number eight in F1 2023, but for this session he was forced to settle for P8.

There were also some further troubles for Fernando Alonso with plenty of work going on around the front of that Aston Martin AMR23, but like on Day One, that did not stop him posting some impressive laps when he was out on the track, his best of a 1:32.969 good enough for P3 in the standings for that first session.

Splitting the Spaniards was an American, Williams’ rookie Logan Sargeant making a very positive impression during his day at the wheel of the FW45, completing well north of 100 laps, the same true for Alfa Romeo’s Zhou.

There was a bit of drama to come right at the end of the session as the FIA went through its flags and systems tests, with drivers not quite on the same page when a practice race start was attempted, Sainz and Hamilton needing some quick reactions to avoid a bizarre early repair bill.

With the topper of both Day One sessions Verstappen back in the car for Friday afternoon, he needed little encouragement to start troubling the top times and soon set one of his own, a 1:31.650 on the C3 tyre to leave Sainz’s effort from the morning in the dust.

Sainz’s Ferrari team-mate Charles Leclerc meanwhile, who had taken over the SF-23, was focusing initially on race runs, as was George Russell, now manning the Mercedes W14.

When Leclerc did set off on a low-fuel run on the C3s, he found himself unable to get within a second of Verstappen, though with the Monegasque having said earlier that everyone is still hiding performance, such times were not as concerning as they may have initially seemed.

Nico Hulkenberg though would have been very happy with his time as he shot up to P2 with a 1:32.466, albeit armed with the C4 tyre.

But just as it seemed like the day was running almost too smoothly, with a little over 90 minutes on Friday’s clock remaining, out came the red flags as Russell lost drive and was forced to park the W14 that was stuck in fourth gear, a hydraulic issue then it seemed.

Mercedes duly confirmed that this was the case, and that it was “highly unlikely” that the W14 would be seen out on the track again in the session.

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After a delay of around 15 minutes, and some dicey moments trying to get that W14 onto the recovery truck, the light would go green again to get the session back underway, Alonso settling back into his P2 spot, but with nearly eight tenths to find on Verstappen.

There was another Dutchman on the move though with the C5 soft tyre, as Nyck de Vries popped the AlphaTauri into P2 as the poorly Mercedes W14 made it back to its garage, De Vries later shaving a couple more tenths off his time to move within six-tenths of the ultimate pace.

Alonso was having none of that though as he returned to P2, a 1:32.205 on the C3 tyre taking Alonso to within 0.555s of Verstappen, further suggesting that this AMR23 could be fighting at the business end of the midfield in F1 2023.

Speaking of fighting at the business end, a 1:32.214 from Zhou on the soft tyre saw the Alfa Romeo driver muscle his way into the top three, before he decided to take all the glory with a 1:31.610 that sent him to the very top with half an hour to go. It was a benchmark that would not be beaten.

There were a few late issues with Williams standing off the FW45 that had been vacated by Sargeant in the pit box, the warning lights triggering a full examination before rolling that car back into the garage, while Zhou was unable to get going as he attempted a practice start, a ghastly noise coming from that C43.

Day Two would end with a fresh attempt at a mock race start, which this time thankfully proceeded without issue.

Day Two timesheet:

1 Zhou Guanyu, Alfa Romeo, 1:31.610, C5 tyres – 133 laps
2 Max Verstappen, Red Bull, 1:31.650, C3 – 47
3 Fernando Alonso, Aston Martin, 1:32.205, C3 – 130
4 Nyck de Vries, AlphaTauri, 1:32.222, C5 – 74
5 Nico Hulkenberg, Haas, 1:32.466, C4 – 68
6 Carlos Sainz, Ferrari, 1:32.486, C3 – 70
7 Logan Sargeant, Williams, 1:32.549, C5 – 154
8 Charles Leclerc, Ferrari, 1:32.725, C3 – 68
9 Oscar Piastri, McLaren, 1:33.175, C3 – 74
10 Pierre Gasly, Alpine, 1:33.186, C3 – 59
11 Kevin Magnussen, Haas, 1:33.442s, C3 – 67
12 Esteban Ocon, Alpine, 1:33.490, C3 – 49
13 George Russell, Mercedes, 1:33.654, C3 – 26
14 Sergio Perez, Red Bull, 1:33.751, Prototype – 76
15 Lewis Hamilton, Mercedes, 1:33.954s, C3 – 72
16 Lando Norris, McLaren, 1:35.522, C2 – 65
17 Yuki Tsunoda, AlphaTauri, 1:35.708, C2 – 85

The article Bahrain test Day Two report: Zhou Guanyu P1, Mercedes trigger red flag appeared first on Planetf1.com.