Perhaps not unexpectedly, the Monaco Grand Prix proved to be the most challenging race of 2017 so far for Mercedes-AMG Petronas Motorsport. Difficulty in balancing the car on the softest of Pirelli's available tyre compounds, the UltraSoft, shaped the team's weekend and limited Valtteri Bottas to fourth place and Lewis Hamilton to seventh.
'We had problems getting the car nicely balanced'
On a more conventional circuit, the race affords the opportunity to overcome such issues to a large extent but, amid the confines of the two-mile ribbon that winds its way through some of the world's most expensive real estate, overtaking is almost impossible and Qualifying dictates all.
Team boss Toto Wolff admitted that, heading into the race, third place behind the two Ferraris was likely to be the best potential outcome. First practice on Thursday morning did not reveal the full extent of the issues the team would face - but track evolution is particularly high in Monte Carlo and in Thursday afternoon's second session both Lewis and Valtteri struggled with set-up and balance, finding it hard to consistently get the car into the right tyre operating 'window.'
"We had problems getting the car nicely balanced, especially in the slow-speed corners," Valtteri explained. "We struggled with rear stability and when the rear is not stable you are not putting energy through the front tyres either. When the rear is stable, the fronts are understeering slightly. That puts more temperature into them and you can carry more speed through the corners, which gains you more energy and more temperature. For some reason, Ferrari seems to have both axles, front and rear, always working, while for us they are not really coming together - not both at the same time or all of the time."
'It was an exceptional performance'
The different approach dictated by the problems Valtteri articulated were clear in tyre preparation for the all-important Qualifying laps on Saturday afternoon. Ferrari, for instance, were able to run warm-up laps 5-6s quicker than Mercedes, with both Valtteri and Lewis having to be very careful not to overheat the rear UltraSofts while attempting to get sufficient temperature into the fronts - all amid the constraints of traffic around the short Monte Carlo lap. Complicating the situation further were the lower tyre pressures specified by Pirelli in the run-up to Monaco.
In the circumstances, Valtteri, who had not yet driven a fully competitive car around Monaco, did a superb job to qualify just 0.05s behind Kimi Räikkönen's first pole position since 2008 and just a hundredth of a second behind championship leader Sebastian Vettel in the second Ferrari.
"It is one of the best Qualifyings I've had - certainly the best lap for me at Monaco," Valtteri acknowledged. "It could have been a completely different Sunday with those extra five hundredths..."
"It was an exceptional performance," Toto agreed, "Valtteri definitely outperformed the car."
In his attempt to do likewise in Q2, Lewis pushed a little too hard going into Massenet, the quick left-hander over the crest approaching Casino Square, and pulled off 'save of the season' to keep his Mercedes out of the barrier. But, his tyres now dirty and losing temperature, he lost all grip on that set and needed to pit for fresh rubber.
'I was devastated'
By the time he had those up to temperature and with time ticking away, Stoffel Vandoorne had crashed his McLaren in the lap's final sector, bringing out the yellow flags and causing Lewis to abort a lap that would have seen him through into Q3 - his previous best time of 1:14.106 from the first Q2 run proving insufficient to make the cut.
"I was devastated," Lewis admitted. "When that happens here in Monaco you know that it's your race done..."
With Valtteri starting behind both Ferraris and Lewis lining up 13th on the grid, Monaco became an exercise in damage limitation for the team. Valtteri made his third strong start in succession - but so short is the run to Sainte Devote, Monaco's first corner, that he had no real opportunity to challenge Vettel and emerged in third place. Lewis, meanwhile, picked up a place when he out-dragged Vandoorne's McLaren off the grid.
With a long projected life for both Pirelli's UltraSoft and Supersoft compound tyres, the race was always going to have just a single pit stop and, unusually given the time taken to generate tyre performance on a new set, it was likely that an 'overcut' could be a better tactical approach than the more regularly adopted 'undercut' - provided that a car was in free air.
'The tyre wear was more than expected'
For Valtteri, the timing of the pit stop and the tactical approach was complicated by a number of factors. Räikkönen had slowed down his pace at the front, closing up the pack, while Valtteri had both Red Bulls close behind. With Verstappen heading for the pits on lap 32 and the Finn trying to manage a problem with an overheating brake caliper, he was not in a position to run high-speed laps at that point.
"We were stuck between a rock and a hard place with the Red Bulls," Toto admitted. "We responded on the next lap when they pitted Verstappen but they left Ricciardo out and he had really strong pace. He was able to run another five laps, with three consecutive laps at 1m16s flat, and came out ahead of us."
"It's disappointing," Valtteri grimaced, "because third place and a podium was possible today. But we were unlucky with Red Bull. While I was stuck behind Sainz after my stop and overheating the brakes, Daniel was setting good lap times. Before the stop I was starting to struggle with the rear tyres and was losing a bit more than the Red Bull guys. The tyre wear was more than expected and, although the numbers that were calculated suggested you could get through the race with one set, there was no way today - at least for us."
After his stellar Qualifying lap, Valtteri acknowledged that the team did not have the kind of race pace that saw race winner Vettel able to turn a 1m15.2s lap with half a tank of fuel just before the half-distance pit stop that gave him the lead and ultimately a third win of 2017. Again, it had been about keeping the tyre in its correct operating window.
'It wasn't out of the window all the time'
"It wasn't out of the window all the time," he explained, "but we were struggling quite a bit with back markers and losing front tyre temperature, then overheating one of the brake calipers and having to adjust the brake bias for that, so I lost quite a bit of time. Finding the rhythm for this track is everything and having to manage things makes that difficult."
One man who certainly was finding his rhythm at this stage, though, was Lewis. Any hopes that he might be able to charge through the field with late braking moves into the harbour front chicane were quickly extinguished. Not only are this year's cars wider but the added downforce of the 2017 regulations gave everyone better traction out of Portier, the corner before Monaco's flat-out tunnel, and better braking stability into the chicane itself. Subsequently, the race did not witness a single successful overtaking move - and Lewis' only opportunity came when the cars ahead of him pitted out of the way.
Finally in free air, Lewis was able to turn in low 1m16s laps on UltraSofts which were by now 40 laps old - that pace getting him up to seventh place when he emerged from his lap 45 pit stop. With the car feeling much more to his liking on the Supersoft tyre, Lewis rapidly closed a 10s gap to Carlos Sainz and was on the Toro Rosso's tail with 20 laps to go.
"I closed the gap up and was on the edge with the brakes. But in terms of utilising what I had, I think my race was good," Lewis said. "I tried to pass Sainz and gave it a couple of stabs. But the chances of passing him were remote, so it was better to bank the points, turn the engine down and live to fight another day. Six points is not what we came here hoping for but I'd like to think they could be important at the end of the year."
'We will work really hard in the next couple of weeks'
Valtteri, meanwhile, had a fleeting chance to recover his podium position after a late race Safety Car when Jenson Button collided with Pascal Wehrlein. At the re-start, Ricciardo glanced the barrier hard at Sainte Devote and Valtteri jinked right as they went up the hill.
"I thought there was a chance on the right but I could see the guard rail coming closer and closer and Daniel closing the gap..." Valtteri smiled. "I could still get back across to the line and keep Max behind but that was my only small opportunity to get third place back. Daniel actually properly hit the wall and can't have been far away from breaking something."
Thus, with fourth and seventh place, the team was left to reflect on a day that saw Ferrari open a 17-point advantage in the Constructors' Championship and Vettel open up a 25-point margin over Lewis in the Drivers' Championship race.
Looking ahead, the team is prioritising a better understanding of the UltraSoft tyre. In Lewis's words: "Coming to Monaco, I thought we had some seriously strong races coming up. But these tyres are a serious unknown. It's only the ultrasoft which is the issue and that is what we are going to try to understand this week. As soon as we get on top of that it gives us a leg-up and a much better position to attack. Montréal has been a great hunting ground for me in the past and we will work really hard in the next couple of weeks to try and get on top of that."