Mercedes's driver George Russell suggested after just two days of testing, he feels Red Bull Racing is "definitely a step ahead."
George Russell completed 122 laps - more than two times the race distance of the Bahrain Grand Prix during his first test with W15 on Wednesday.
The 25-year-old's progress was interrupted by a power-unit-related issue during the morning session. Still, overall, the tests went pretty smoothly for him, especially compared to William's drivers, who completed 61 laps altogether.
At the end of the Wednesday testing, Russell's best time of the day was 1:34.109, which was 2.765 seconds slower than the fastest lap time set by Max Verstappen in Red Bull.
While the Mercedes driver asserted that Mercedes's focus wasn't at all on setting the fastest lap time, according to BBC, he suggested today that Red Bull is a step ahead of every single F1 team.
"Red Bull are the favourites and definitely a step ahead of everyone else. That was to be expected."
In fact, Max Verstappen gapped everyone by more than a second during the first day of testing, but the advisor of the Austrian team, Helmut Marko, stated the pace advantage is lower than it might seem.
The 80-year-old expects around 3-tenths per lap advantage. While Russell does feel better about his Mercedes, he also sees that the team from Milton Keynes is still "quite a bit ahead."
"In terms of feeling, our car feels a lot better than last year. My initial feeling is that Red Bull remain quite a bit ahead."
Red Bull seems to have hit the ground running already in a perfect spot, but Mercedes still needs a lot of adjustment before the first race of the season (which takes place next Saturday), as the 25-year-old added:
"Red Bull are already in that sweet spot but hopefully we can close the gap. But it is going to take a lot of hard work to do it."