The Canadian Grand Prix may have been a forgettable race in terms of on-track action, but the result underlines how tight this year's championship fight will be.
On a circuit where everybody expected Mercedes to have the fastest car, Ferrari emerged with a comfortable victory following a hard-fought pole position. As ever in Formula One, the smallest of margins made a big difference in the end result but Mercedes was left kicking itself after its two biggest setbacks appeared to be self-inflicted.
"We were coming to Montreal expecting our car to be really strong and we're leaving Montreal seeing we haven't been where we thought we should be," Mercedes team boss Toto Wolff said after the race. "I think this is a major wake up call for every single member of the team. Everybody needs to assess how to improve performance in order to optimise on those marginal gains, because those marginal gains are going to make all the difference."
The first and most obvious setback for Mercedes this weekend was the failure to deliver its latest specification of engine. Each driver has just three engines to last the year before incurring grid penalties and the teams try to make sure the introduction of each new component on the car coincides with the latest performance updates from the factory.
For the simple reason that the Canadian Grand Prix takes place on a power-sensitive circuit one third of the way through the season, all four engine manufacturers had targeted their first major hardware upgrade this weekend. But while its rivals all delivered on their promised steps in performance, Mercedes' upgrade had to be delayed until the next race in France.
Data from the engine's final dyno run in Brixworth prompted concerns from a reliability point of view, especially as a failure at this stage of the season would likely result in a grid penalty later in the year. But while delaying the upgrade until France was the prudent decision, it came with some obvious downsides as all Mercedes-powered cars then had to start the weekend with a six-race-old engine, which was not only down on power but also nudging its intended mileage limit.
The plan had been to give the six-race old engine its final outing in Hungary in August -- home of one of the least power-sensitive circuits on the calendar -- but instead it was tasked with completing a race at one of F1's most power-sensitive circuits in Montreal. Although remarkably efficient, powerful and reliable given their specification, an F1 engine will lose some of its potency over the course of its life cycle.
Conservative estimates put the six-race-old Mercedes engines at a 10bhp disadvantage compared to a fresh unit and combined with the upgrade Sebastian Vettel received from his phase two Ferrari engine, the swing in power unit performance between the two teams was thought to be in the region of 20-25bhp. On a track like Montreal, that is enough to account for Valtteri Bottas's 0.093s gap to pole position, which ultimately proved crucial as Vettel controlled the pace from the front of the field.
In the race, Lewis Hamilton's Mercedes engine lost even more power when a mechanical issue led to overheating and some very serious reliability concerns. From behind the wheel Hamilton experienced several power dropouts and was happy just to see the chequered flag by the end of the race.
"It was huge, I mean I thought the engine was going to fail," he said after the race. "Straight from the start, got up to Turn 2, the power started dropping out so there was a lot of hesitations and the engine dropping in power so I thought the engine was going to blow.
"Ultimately it could be a lot worse. I could have had a DNF and lost 25 points, however in two races we've lost 18 points or whatever it is. We've definitely fallen behind a little bit in that respect but I am just grateful the engine made it through today and that I got to see the distance."
The overheating engine also forced Hamilton to pit early so that his team could rip off some of the bodywork around the cockpit and relieve some of the heat building up under the engine cover. To add to his issues, that put him on a compromised strategy as he saw none of the benefit of running longer into the race on the ultra-soft tyre and lost a place to Red Bull's Daniel Ricciardo around the pit stop itself.
But while Mercedes slipped up, Ferrari should also be applauded for delivering an impressive step in performance from its own engine. After holding a small edge in power throughout the first six races of the season, Ferrari extended its advantage in Canada. What's more, by the end of the race Bottas was far more marginal on fuel than Vettel, hinting that the Ferrari upgrade has also addressed the excessive fuel consumption the team faced at some of the opening rounds. Whether Mercedes can match Ferrari when its upgrade finally arrives in France remains to be seen, but for the first time since the start of the turbo-hybrid era in 2014 the Mercedes engine was a clear second best to one of its rivals.
More tyre troubles
The second of Mercedes' issues in Canada was more familiar to the team. Extracting performance from Pirelli's tyres, especially the softest compounds in the range, has been a reoccurring weakness for the team in recent years, but in Montreal it did itself no favours.
Unlike rival teams that opted for between seven and eight sets of the hyper-soft compound per car, Mercedes limited its drivers to five sets each over the race weekend. Considering at least three of those sets were required for qualifying, that left just two sets to experiment with in practice. As a result, Mercedes didn't use the hyper-softs at all during Friday practice, leaving just the Saturday morning practice session for the drivers to adapt their setups to the tyre they would be qualifying on two hours later.
Tyre allocations have to be selected 14 weeks in advance of a flyaway race like Canada, meaning all teams had to make their choice for Montreal at the end of pre-season testing. Mercedes had opted against running the hyper-soft compound throughout pre-season testing and was therefore basing its decision for Canada on information it had gathered at the end-of-season test in Abu Dhabi last year.
That information indicated that the hyper-soft would be easy to switch on over a single lap but would not be a good race tyre. As a result, Mercedes' strategists chose to stock up on the ultra-soft and super-soft tyres in the knowledge they would not be using the hyper-soft in the race. While that turned out to be the case, Hamilton was not able to get the most from the hyper-soft in qualifying and twice made mistakes on his Q3 laps at Turn 10. Had he spent more time on the compound in practice there was a feeling that he might have got more from the tyre when it mattered.
"There's not one single reason why we haven't performed like we should but certainly all of us in the team are aware that based on the findings of Abu Dhabi we were guided in the wrong direction," Wolff explained. "Having had one, or two more sets to accommodate the drivers better for qualifying would have may be, would have may be helped us secure pole position. But I'm saying may be because we don't know, it's not only one factor.
"It's always those many factors that all contribute to solid performance. But I guess that putting Lewis on the hyper on Saturday morning was probably too late. But we are aware of that, and that played a role."
How worried should Mercedes be?
While Mercedes missed out on a potential victory in Canada, the competitive situation is likely to change again at the next round in France. Although dyno testing and development work is ongoing to provide a fix for the reliability issues on the phase two engine, it is expected to feature in Paul Ricard. What's more, the troublesome hyper-soft compound won't be seen again until the Singapore Grand Prix, with the ultra-soft, super-soft and soft tyres set to feature in France combined with the thinner gauge rubber that Mercedes excelled on at last month's Spanish Grand Prix.
In the meantime, Vettel leads the championship by a single point and, having secured pole position at four of the seven races this season, appears to have the faster car. But as the grand prix in Montreal showed, a few small mistakes can result in a big swing in performance this year and Hamilton is convinced it will go both ways before the end of the year.
"I think Ferrari have had a slightly better package all round, they've been doing a slightly better job so we've got to do more," he said. "We've got to keep working, which I know the guys are, and I just think we need to stay positive. There's no reason to lose control.
"We just keep doing what we are doing, keep our heads down, keep motivated and keep pushing because they will falter. We need to keep applying the pressure, we didn't this weekend but I'm really going to make sure we come back stronger at the next race."