F1 testing: Red Bull driver Isack Hadjar surprised with strong performance on opening day in Barcelona as George Russell also impressed | F1 News

Isack Hadjar admitted his surprise at Red Bull's “productive” and “smooth” performance after topping the timesheets on the first day of Formula 1 pre-season testing in Barcelona.

Although lap times were not considered too important as the teams ran their all-new 2026 cars together for the first time – following changes to powertrain and chassis regulations – there were doubts about how Red Bull would fare as they embarked on a maiden campaign producing their own engine.

Hadjar, who was promoted alongside Max Verstappen after impressing for Racing Bulls during his rookie campaign, set a time of 1:18.159s to end the day just over half a second ahead of Mercedes' George Russell.

Just as impressive, if not more, than Hadjar's lead time were the 107 laps the Frenchman was able to rack up, with Liam Lawson adding a further 88 for Racing Bulls, the only other team on the grid to use Red Bull's premier F1 power unit.

Hadjar said: “It was quite productive, surprisingly. We managed to do a lot more laps than expected.”

“Everything went pretty well. We only had minor issues, so that's pretty impressive considering it's our first day with our own engine. Everything went really well.”

Asked specifically about the powertrain's performance, Hadjar added: “Honestly, it's pretty decent for our first day.

“It doesn't feel too far from what I'm used to, at least in my first season, on all the upshifts and downshifts. It was ok. There's still a few things to fine-tune, but it's solid.”

Russell impressed by Red Bull

As Mercedes continues its strong start to the year with Kimi Antonelli and Russell combining for 149 laps on Monday, the Briton admitted he was impressed with Red Bull's performance.

Mercedes managed a worrying total of 67 laps during a filming day at Silverstone last week, suggesting they are very well prepared for a season many consider them favorites for, and have maintained that solidity despite being edged out by Red Bull at Barcelona.

“We're very happy with today, but I was quite impressed with a number of other teams, to be honest,” said Russell, who took over from Antonelli for Monday afternoon's session.

“The Red Bull-powered teams, with a completely new powerplant, and it's a completely new team from a powertrain perspective, and they had a really smooth day with two cars. Audi did some good laps in there as well. Haas did the most laps of anyone with a Ferrari engine.”

Russell appears to suggest there is unlikely to be a repeat of the last time new engines were introduced in 2014, when Mercedes won eight successive constructors' titles after being well ahead of the rest of the field in early test runs of that era.

He added: “It's not quite the atmosphere of 2014, where half the grid broke down and had lots of problems. I think Formula 1 has evolved so much since then and the standard is so high in every aspect.”

“It was pretty impressive to see all the teams as a whole get a lot of laps under their belts on day one.”

Antonelli: Mercedes very pleasant to drive

Antonelli has given a favorable review of the Mercedes W17 as he prepares for his second season with the team.

“It was a very interesting morning, very nice to be back in the car,” Antonelli said.

“It's a huge learning curve. We've been trying to tune the powertrain and the car, and obviously this afternoon the car has improved a lot, and it's a constant learning.”

“The car is beautiful. It's very pleasant to drive and obviously on the powertrain side, it's a little different from what we had last year, it requires a little more management but everything is doable.”

“On the powertrain side, the team has done a very good job and the handling, which was a big question mark, seems to be good so far.”

“Obviously it's just the beginning, and that's why with the rolling we'll find out a lot more about the car and the powertrain and we'll be able to see where it's lacking or where it's really good, but so far the package feels good.”

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