Yuki Tsunoda said he found Red Bull's car "more tricky" to handle than he had expected during his first practice sessions for the team at the Japanese Grand Prix.

Tsunoda was promoted from Racing Bulls last week to replace Liam Lawson with Red Bull, who had failed to score any points in his first two races of the season. 

The Japanese driver initially appeared to fare well as he finished one place - and a tenth of a second - behind team-mate and world champion Max Verstappen. 

Tsunoda then finished 18th in an unrepresentative second session interrupted by four red flags, failing to complete a qualifying simulation on soft tyres.

For obvious reasons, Lawson's brief stint at Red Bull has cast doubt on the drivability of the RB21, and Tsunoda revealed he would be busy with engineers on Friday. 

"FP1 was better than expected. A good start for myself," Tsunoda said. "FP2 I didn't even set a lap time. Lots of work to do.

"Maybe slightly struggled or there's something we have to look into the data for FP2 but so far it was okay, I just need to build the confidence more."

Tsunoda had said earlier this week in his first interviews since joining the team that he had enjoyed driving the RB21 on the simulator and thought it might suit his driving style.

But on Friday, he said: "It's a bit different to the simulator, what I felt. Maybe more than expected in terms of car feeling.

"I knew it would always be a bit different in the real car and it was a bit more exaggerated in the real car, feeling a bit more tricky."

The Bulls blossomed into session

The White Bulls came in two by two, finishing in P5 and P6 #F1 || #JapaneseGP 🇯🇵 pic.twitter.com/rVDMLxrmeb

— Oracle Red Bull Racing | オラクル・レッドブルレーシング (@redbullracing) April 4, 2025

On the opposite side of the Red Bull garage, Verstappen also struggled with the RB21's balance.

In what is becoming a recurring theme for the Milton Keynes outfit, Friday practice exposed a series of fundamental problems that have seen them struggle in recent weeks. 

The Dutchman finished eighth in the second practice session, with Red Bull's struggles further highlighted as both Racing Bulls cars finished ahead of them. 

Isack Hadjar was third, while Lawson claimed fifth on his return to the junior squad.

"It was quite chaotic for everyone out there with all the red flags," Verstappen said. "Today has been quite difficult for me.

"We tried a lot of different things with the car but it seems like a lot of things are not really clicking at the moment, so it's quite difficult to put the lap down.

"You need a lot of confidence and commitment around here. At the moment, I don't feel like I can use that so I still have quite a bit of work to do."