Extra day vital for Mercedes to understand gap

Monaco is the only race on the calendar that features a rest day, with the first two practice sessions on Thursday then final practice and qualifying on Saturday after a pause on Friday.

Daniel Ricciardo's Red Bull ended second practice 0.606 seconds clear of Mercedes and Rosberg admitted that gap was more than a case of his team running conservative engine modes.

Mercedes did not run the ultra-soft for the first time until Thursday practice in Monaco and Rosberg feels the team will need the extra time afforded to it to make inroads for qualifying.

"In this case, it's great that we have an extra day with the situation we find ourselves in," said Rosberg, who was speaking at an event to highlight the collaboration between Mercedes and its wireless technology partner Qualcomm.

"There is more time to dig and try and find some more performance. It's important we do our homework.

"We have so much information on the tyres with temperature sensors here, there and everywhere so we can create an accurate picture of what tyres are doing on track.

"We are looking to extract a bit more out of these tyres, which we're running for the first time in Monaco.

"We want to see if we can get a bit more out of them for qualifying because the Red Bulls were doing something pretty good and we need to try and understand."

Mercedes executive technical director Paddy Lowe said it was still unclear on what lap the ultra-soft would give its best performance.

"We have learned it works and we are still in the process of finding out if it's a lap one or lap two tyre," he said.

"We have seen teams trying different routes. It's actually somewhere between the two.

"The circuit may evolve over the weekend and maybe reach a point of being a lap one tyre.

"Some of the homework Nico was talking about is to dig a bit deeper than you can do in real time and understand what we can do differently on Saturday to get that tyre in the perfect state for that final lap in Q3."