Mercedes still unsure about the performance of its recent upgrades

Following two tough races, Mercedes is eager to evaluate whether its new floor that was first introduced at Spa and then at Zandvoort, had a negative impact on the performance of its W15.

Mercedes secured three victories in four races before the summer break, but it has slightly slipped down the pecking order behind McLaren, Ferrari and Red Bull in the last two rounds.

The Brackley-based outfit introduced a new floor on its W15 at the Belgian Grand Prix, but it abandoned the modified part at Spa, fearing from negative consequences on the balance of its car.

The Dutch Grand Prix finally saw Mercedes bolt the new floor on its car, but the Zandvoort event saw the German-British outfit suffer a slight drop in performance compared to its direct rivals.

After a tough Italian Grand Prix, Mercedes' Trackside Engineering Director Andrew Shovlin noted that the team is trying to understand if the lack of progress is due to the new parts or the layout of the last two tracks.

"We have made several comparisons between the packages and mainly between the two upgrades, and we are sure that this generates the load we expect.

"The most difficult question we have to answer is: is there anything subtle about the handling features that this package could do that we didn't foresee. It may be just a normal variation from track to track, but that's what we'll check in the coming days."

Shovlin also mentioned that new updates are coming, stating that "there are other updates that we will introduce."

Lewis Hamilton was involved in a battle with Ferrari driver Carlos Sainz after the first rounds of pit stops, but the Briton was forced to make a second pit stop due to graining, while the Spaniard managed to complete the race distance with only one tyre change.

Reflecting on the closely-matched qualifying session and the two-stop strategy, Shovlin said that the W15 was very competitive in low-fuel configuration, but it slightly lost pace on Sunday.

"At the last corner, we were half a tenth from Lando, but then the last curve for Lewis did not go particularly well. If it hadn't been for that, he could easily have been in the front row if not in the running for pole."

During the race, 'Lewis was behind Carlos and it made no difference if he made two or one stop, because Carlos had fresher tires. It was unlikely that we would be able to pass with the same strategy, so we decided to make two stops, to do something different."