The team may have taken the lead in the 2018 Constructors' Championship for the first time when Valtteri Bottas and Lewis Hamilton finished second and fourth respectively in the Chinese Grand Prix...
But round three of this year's Formula One World Championship at the Shanghai International Circuit proved what a tough task the team faces if it is to achieve a fifth straight title success, with stern opposition from both Ferrari and Red Bull Racing
Lewis went into the weekend chasing a sixth victory and seventh pole position in Shanghai and early indications looked good when he topped both sessions of free practice on Friday, setting competitive race-run times in the process. The outlook changed on Saturday, however, when much cooler track temperatures made a "night and day difference" to the feel of the W09.
The extent of the change was demonstrated by the margin Ferrari enjoyed in locking out the grid's front row. Sebastian Vettel took pole with a lap in 1:31.095, backed up by Kimi Räikkönen on 1:31.182, while the best times Valtteri and Lewis could manage en route to the second row were 1:31.625 and 1:31.675 respectively, just over a tenth quicker than Max Verstappen's fifth-placed Red Bull.
"It was about getting the tyre in the right window," Toto Wolff explained. "What we suffered from overheating in Bahrain happened the other way. The tyres (Pirelli's UltraSoft compound) were on the cool side, with Lewis' temperatures colder than Valtteri's, and we lacked grip. By contrast, the Ferraris looked like they were on rails, similar to us in Melbourne (scene of the season's opening race three weeks ago)."
But, as Toto pointed out, all was not lost. Valtteri and Lewis, in company with both Ferrari drivers, used the Soft compound tyre to set their Q2 times and would therefore start the race on the yellow-walled Pirelli - and it was unlikely that the UltraSoft would be seen on either car in the race. The Red Bulls, however, would start from the third row on the UltraSoft and, with temperatures on race day forecast to be hotter, would not necessarily have the flexibility to run a one-stop race - the strategy that Pirelli simulations indicated would be quickest.
The start was more important than ever for the race prospects of Valtteri and Lewis and, when Vettel moved right to stop Räikkönen challenging down the inside into Turn 1, Valtteri was quick to take advantage and go around the outside of the No.7 Ferrari into Shanghai's ever-tightening 'snail' section of opening corners.
Lewis, meanwhile, starting on the same side of the grid as Räikkönen, found himself boxed in, dropping a place to Verstappen's Red Bull and sitting fifth across the line at the end of the opening lap.
Vettel established a 2s advantage over the opening couple of laps and then appeared to start managing his tyres. The Ferrari led Valtteri by 2.5s after 10 laps and then, 15 laps into the 56-lap race, had the lead out to 3.8s as the first pit stop window neared. Interestingly, over the next three laps, Vettel's lap times dropped by almost half a second, indicating either that Ferrari was suffering increased tyre degradation on the Soft Pirelli or that they perhaps underestimated the potential power of the undercut. At the end of lap 18, Valtteri was back within 3.5s.
But, a lap earlier, Red Bull triggered the pit action when the team double-stopped third-placed Verstappen and sixth-placed Ricciardo. Verstappen had managed to stay within 6s of Valtteri on the UltraSoft tyre and get it far enough to potentially run a one-stop race, meaning that he was far from out of the picture. Team mate Ricciardo, meanwhile, had run his opening stint behind Lewis and was still within 2s of car No.44 as he headed for the pits just 6s behind Verstappen.
Double-stopping with both cars can pay strategic dividends but is risky in as far as any problem experienced with the first car can be compounded in delaying the second. Red Bull, however, managed two quick stops, which forced the team to respond by pitting Lewis next time around after 18 laps to combat the undercut. It was going to be tight but a good 'in' lap from Lewis and an efficient stop kept him ahead of Ricciardo.
The team brought Valtteri in next time around, spotting an outside chance of undercutting Vettel as Ferrari left the race leader out. Valtteri was told it would be extremely close and gave it everything. The team still needed all its stars to align and they did: an incredible Mercedes pit stop - around 1.8s to the point when Valtteri got the green light to go - was right up there with the best and was accompanied by a perfectly executed 'out lap' from Valtteri.
The Ferrari stop when Vettel pitted a lap later was almost a second slower - understandable, perhaps, given the issues of a week earlier in Bahrain when crew man Francesco Cigorini suffered a broken leg as he was hit by the departing Räikkönen. As Vettel re-joined, Valtteri was ahead of him!
Ferrari, meanwhile, left Räikkönen out and at the end of lap 21, with 35 to go, Kimi led Valtteri by 8.5s with Vettel just over a second behind the No.77 Mercedes, then a 6s gap to Verstappen, who had Lewis 2s further behind, with Ricciardo a further 4s in arrears.
On his fresh Medium compound Pirellis, Valtteri was almost 2s per lap quicker than Räikkönen on his old Softs and, by lap 26, was within DRS range of the leading Ferrari but facing a potentially tricky situation with Vettel also breathing down his neck.
"When I was closing in on Kimi I could see what they (Ferrari) was planning," Valtteri smiled. "In their position we would have done the same. I think Kimi was definitively trying to slow me down, so Sebastian got close to me but luckily it didn't help him enough to get him through. Kimi was really struggling with his old tyres."
Taking full advantage, Valtteri made the second decisive pass of his compatriot to re-take the race lead on lap 27 and managed to be late enough on the brakes at the end of the back straight into Turn 14 to prevent Vettel launching a DRS-assisted overtaking attempt down his inside. Räikkönen, his challenge blunted by such a long opening stint, was then immediately brought in for a swap onto the Medium compound Pirellis. Valtteri, so far, had been wheel-perfect all afternoon - but Lady Luck was about to conspire against him.
Further down the field Pierre Gasly, who had already pitted, was on tyres 10 laps fresher than Toro Rosso team mate Brendon Hartley and under the impression that the Kiwi was leaving the door open for him at the Turn 14 hairpin. Hartley, however, was planning to let Gasly through on exit, as he'd done earlier in the race, and turned in. The Toro Rossos hit each other on lap 29 and left shards of carbon fibre bodywork on the track.
Renault driver Carlos Sainz was among those who radioed in to say there was enough debris on the circuit to warrant a Safety Car and, on lap 31, it was deployed. Unfortunately for Valtteri, he and Vettel's second-placed Ferrari had already passed the pit entry and so there was no opportunity to stop and go onto another set of the Soft compound tyre to counter having their lead erased by the Safety Car.
With Verstappen 5s behind Vettel on the road, Red Bull had just enough time to call the Dutchman into the pits to go back onto the Softs. Lewis, still just 2s behind Verstappen, stayed out, while Ricciardo, from 4s behind Lewis, was also called in to go back onto the faster yellow-walled Pirelli, losing just one place to Räikkönen in the process as Red Bull performed its second trouble-free double stop of the afternoon.
With 21 racing laps left when the Safety Car came in, the remainder of the Chinese Grand Prix was going to be fascinating. Valtteri led on Medium compound Pirellis a lap older than Vettel's. Then came Lewis on the same compound but two laps older than the Ferraris, followed by Verstappen on new Soft compound Pirellis - a threat, obviously - then Räikkönen on relatively new Mediums, who might have been expected to delay the progress of Ricciardo, also on new Softs.
"Am I right thinking there's guys on fresh tyres right behind me?" Lewis asked over the radio.
"Affirmative, Lewis," came the response.
With Valtteri and Vettel unable to pit, why had Mercedes chosen not to mirror Red Bull's move with Verstappen and roll the dice by bringing Lewis in for a set of the Soft compound Pirellis?
Multiple factors had driven that decision. Firstly, Mercedes strategists knew that if they had responded to Verstappen's stop by following him in, they would emerge behind. Further, had they pitted Lewis, Red Bull may well have chosen to leave Ricciardo out, so there was the potential of losing one track position to the Australian.
On top of that, Räikkönen, on relatively fresh Mediums after his late stop, was also right around the window where there was a significant risk of losing another position. And, on the evidence witnessed in the race so far, overtaking did not appear easy.
With the Medium compound performing relatively strongly on the W09 and within its predicted stint life even running to the end of the race, the potential risk versus reward was not considered worthwhile. Racing hard again, Lewis quickly came under pressure from Verstappen but it did seem optimistic when Max tried to pass the Mercedes around the outside of the high-speed Turn 7 on lap 39!
"I didn't even see him there," Lewis said. "I was doing the corner normally and when I watch the replay I don't really understand what he was up to there..."
Asked if he'd ever overtaken anyone there in all the time he'd raced in Shanghai, Lewis replied, "certainly not a top driver."
Verstappen indeed ran wide onto the grass and lost a place to Red Bull team mate Ricciardo, who on lap 40 pulled off a fine late-braking move into the Turn 14 hairpin to take third from Lewis.
Vettel's second-placed Ferrari fell victim to the Red Bull two laps later, before Ricciardo sliced down the inside of Valtteri to take the lead at Turn 6 on lap 45.
"He was really closing quickly," Valtteri said. "He had a really strong car and fresh tyres too. Seeing the pace at which he disappeared afterwards, there was a big difference. I went to defend into Turn 6, but it's always a compromise. If you go too extreme, then he's definitively going to get you on the exit if he does the normal line into it. Daniel also tends to find space on the inside even though you do defend. But, given the pace he had, it was just a matter of time anyway."
Verstappen had not been discouraged by his moment at Turn 7 and passed Lewis three laps later. Vettel was next on his radar but the pair made contact at Turn 14 on lap 43 and spun, with race stewards awarding Verstappen a 10s penalty for the incident. In the resulting confusion, Lewis lost third place to Räikkönen.
"As I came to the apex I saw them both facing me. I couldn't do the tighter turn that Kimi did, and had to go left, which was unfortunate and cost me the place," he explained.
A fantastically entertaining race for the neutral finished with Ricciardo taking his sixth Grand Prix win 8.8s clear of a really strong performance from Valtteri, who beat Räikkönen by 0.8s. On a day when he had not felt at one with the car and had to eke out a set of Medium compound Pirellis for 38 laps, Lewis considered himself fortunate to make an eight-point Championship gain on Vettel, who limped home eighth having been passed by Nico Hülkenberg and Fernando Alonso in the closing laps.
With the benefit of hindsight supplied by Ricciardo's win, the team may have rolled the dice and pitted Lewis as well - but remained unconvinced that the W09 would have afforded them similar pace to the Red Bull on the Soft compound Pirelli; Ricciardo set an impressive 1:35.785 on the race's penultimate lap.
Despite Ricciardo's fine drive, you had to feel for Valtteri, who had everything under control before a Safety Car he had no chance of responding to. Vettel, in a similar position, later pointed out that after a Safety Car in the 2014 Hungarian GP changed the outcome of the race, he was hopeful that future deployments would be timed to avoid such situations, but that had not been the case in China.
"The overriding feeling is obviously disappointment because we are here to win," Valtteri said, "and we didn't win today even though we were leading for quite a big part of the race. I managed to take all the opportunities that came up and around the pit stop the team did a perfect job. Then, obviously, things changed and there was a different outcome."
Lewis, meanwhile, reflected: "We lacked pace from Saturday onwards. The car just felt very unstable and didn't really turn in at a lot of corners. We've lost performance since Melbourne and are second or third fastest team at the moment. There's improvements to make but this team has shown to be great at staying united and pushing as hard as possible."
Despite still seeking its first victory of 2018, the team leads the Constructors' Championship with 85 points to Ferrari's 84, with Red Bull on 55. In the Drivers' Championship, Vettel has 54 points to Lewis' 45 and Valtteri's 40. Shanghai winner Ricciardo has 37 and Räikkönen, 30.
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