From the opening laps of first practice it was clear Mercedes would have an advantage in Monaco. As rival drivers ran up close or even nudged the barriers, both Lewis Hamilton and Valtteri Bottas had track to spare as they traded fastest times at the top of the timesheets. Confidence is key on the streets of Monaco and from trackside it was obvious both drivers had plenty.
By second practice, they started to stretch their legs. Even on the medium compound, Mercedes were able to match Ferrari on the softs and when Bottas and Hamilton switched to the fastest compound they emerged 0.7s quicker than Sebastian Vettel in third. Vettel had a clean lap without traffic -- the difference in lap time was down to pure performance.
Throughout the season the Mercedes has proved the faster of the two cars in slow speed corners. Considering the W10 has the longest wheelbase in the pit lane, it seems somewhat counterintuitive -- and in stark contrast to recent years when the relatively long Mercedes has struggled in Monaco -- but under the 2019 regulations the world champions have turned one of their biggest weaknesses into a strength. Considering the Monaco Grand Prix is so often won from the front row and into the first corner, it's hard to predict anything other than a Mercedes victory on Sunday if the race runs normally.
Any hope that Ferrari's recent struggles had been solved at last week's in-season test in Barcelona were thrown out the window almost from the get-go in Monaco. A difficulty getting the tyres up to the perfect temperature for peak performance was only exaggerated in Monaco, where a lack of high-speed corners makes it even harder to generate heat in the tyres.
Charles Leclerc struggled more than Vettel, finishing the session in 10th place and 1.2s off the pace, as he visibly struggled to lean on his front tyres for grip and hit traffic on his hot lap. In Monaco, that creates a downward spiral of performance as the lack of grip rips into the confidence of the driver just as he needs to push to the limit to bring the tyres alive.
"To be quick around here you have to explore the limits of the track to the last centimetre but doing that without hitting the Armco is not easy," Leclerc said after the session. "But we have to run as close to the barriers as possible and also get the tyres into the right temperature window which seems to be complicated this weekend."
"What we are lacking is grip from the tyres because we are not able to make them work properly," team principal Mattia Binotto added. "That is down to an interaction of aero and mechanical and overall it's a balance and you may set up your car to be strong in high-speed and you miss some performance in low speed, but if a car is well balanced it works in high-, medium- and low-speed, so what we are lacking somehow is the optimum in all the conditions."
While Ferrari has gone to great lengths to say it is not blaming changes to the tyres over the winter for its 2019 struggles, the fact that the tyres are now harder to get up to temperature is at the core of the team's issues in Monaco. Thinner tread on the 2019 tyres means they do not retain heat in the same way as they did in 2018, making the rubber less prone to blistering -- as the teams had requested -- but harder to keep at the right temperature. While Mercedes has found a way to keep its tyres in the right operating window, Ferrari is struggling and Binotto admits the car is fundamentally lacking downforce compared to its main rival.
"The tyres this season are quite different to the ones of last year -- no blame, it is only a matter of fact," he said. "The main difference is last year we had a very good warm up on the tyres and we were focused on cooling the tyres as much as we could to keep them working because the lower the temperature, the better the grip. The tyres of this season are quite different in this respect and warm-up is a lot more difficult.
"What we call the window -- the temperature you target to get the best grip from the tyres themselves -- in order to achieve that you need to heat up the tyres. So instead of cooling them down [as we did last year], you need to heat them up.
"How can you achieve that? Certainly you can achieve it through braking temperatures, rims cooling, but overall it is downforce. And not only does the downforce add absolute value, but it is how you balance the downforce high-speed to low-speed -- it may be as well how you target your development in terms of efficiency versus maximum downforce. I think we have got a car that is somehow quite efficient -- you can see it on the straights -- but it doesn't mean we have the highest downforce in the pit lane."
With Ferrari struggling to mount a convincing challenge to Mercedes, Max Verstappen looked like the biggest threat after the first practice session as he managed to split Hamilton and Bottas. But in FP2 a piece of debris went into the air intake of his Red Bull and damaged a radiator. The resulting water leak took most of the session to repair and by the time he re-emerged, he complained of a lack of grip and struggled to set a quick time as everyone else was focusing on heavy-fuel running. The result was a lap time 0.934s off the pace, but while the margin to Mercedes is large, a clean Saturday should see Verstappen lining up third on the grid.
Verstappen's radiator problem meant he did not complete any representative heavy fuel running, but the times set by teammate Pierre Gasly should give Red Bull reason to be optimistic. His average lap time over 10 laps on the soft compound was a 1:15.112 compared to a 1:14.881 average for Lewis Hamilton over 12 laps and a 1:16.079 average for Charles Leclerc over 11 laps. True, Red Bull might not be able to match Mercedes in a straight fight, but if they can get ahead at the start or take advantage of a Safety Car, the pace shown by Gasly -- and the fact Verstappen has been consistently quicker this year -- could mean they are quick enough to make a fight of it.
Once again, the midfield looks remarkably tight, with traffic in qualifying and the resulting loss in tyre temperature likely to dictate the grid. Alex Albon backed up his impressive fifth place finish with two solid long runs on the softs and Alfa Romeo also looked competitive after its cars finished eighth and ninth. However, if a driver makes one mistake in qualifying, it doesn't matter how good his Thursday practice pace was as overtaking in Monaco is almost impossible.