Daniel Ricciardo has revealed he "couldn’t really extract" any pace from his new McLaren at the season-opening Bahrain Grand Prix.
The Australian driver finished seventh on his debut for McLaren after signing a lucrative three-year deal to join the British team.
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Teammate Lando Norris narrowly missed out on a podium finish, coming fourth to upstage his elder statesman.
Speaking to the F1 website after the race, Ricciardo said he was happy overall with how the weekend went, but disappointed with the race itself.
“I would say if I [take] the weekend as a whole, I’m pretty happy,” Ricciardo said.
“But if I just focus on the race itself, I struggled quite a bit in the race actually.
"I couldn’t really extract the pace form the car and when I did, I could do it for one or two laps and then it would quickly drop off again with the tyres and the balance, so I just didn’t feel like I had a good race performance, or race package.
“Obviously it’s still new to me, so I’m sure there’s going to be a lot of homework for me to do personally to obviously keep getting better."
Ricciardo had out-qualified Norris and started the race one spot ahead of his teammate in sixth.
However the Australian driver couldn't recover after a minor bingle early in the race.
Nevertheless, McLaren are sitting third in the constructors' championship after the first race thanks to Ricciardo and Norris' combined 18 points.
Lewis Hamilton pips Verstappen in nail-biter
Lewis Hamilton won the season-opening race for Mercedes after an epic, knife-edge battle with Red Bull's Max Verstappen over the final laps.
Verstappen, who passed Hamilton with four laps to go only to have to hand back the lead for going off the track, finished a mere 0.74 seconds behind after starting on pole position.
Hamilton's teammate Valtteri Bottas was a distant third but gained a bonus point for fastest lap.
"Wow, what a difficult race that was," said Hamilton, who started second on the grid and took another of Michael Schumacher's all-time records with his 5112nd race lap led.
"Max was all over me right at the end but I just about managed to hold him off. It was one of the hardest races I've had for a while."
Verstappen appeared to have won the race after passing Hamilton around the outside of the fourth turn with just three laps remaining.
But the Dutchman was instructed by his team to give the position back to Hamilton, fearing their star driver would be penalised for running off the track.
Verstappen's new Mexican teammate Sergio Perez went from starting in the pit lane, after his car had stopped on the formation lap, to fifth place.
Ferrari's Charles Leclerc was sixth and Spaniard Carlos Sainz finished eighth in his first race for Ferrari.
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