Renault racing director Frederic Vasseur has dismissed rumours Jolyon Palmer could be dropped, insisting the Grove-squad is "happy" and "committed" to its current line-up.

Palmer has had a mixed start, and after a good debut in Australia, struggled in Bahrain and China, although he was happier in Russia last weekend after the team changed the floor on his car.

Nevertheless, with Sergey Sirotkin and Mercedes protege Esteban Ocon waiting in the wings - the former running in FP1 in Russia, while the latter will run in first practice in Spain, as well as in the post-event test alongside Kevin Magnussen, it is clear the regie is not without options.

"We have a strong line-up and one we're happy with and committed to," Vasseur said. "Kevin has performed very well in his return to Formula 1 and Jolyon is approaching his rookie season in a clear and methodical manner.

"It's true that Jolyon had a couple of races where he didn't deliver as he wanted, equally this is natural in a driver's first season; he's learning and making strong progress."

Quizzed on Sirotkin and Ocon, Vasseur added: "We saw Sergey Sirotkin do a very good job in FP1 in Russia and we will see Esteban Ocon take to the wheel in Barcelona."

Meanwhile, looking to Spanish Grand Prix itself, Vasseur isn't expecting another top-ten necessarily, despite Magnussen's fine seventh place in Russia.

"It's no secret, we still have plenty of work to do. That will be the story all year. Russia was a good weekend for us as we saw the whole team deliver and our first points of the year were a result. That was great for everyone and a good reward for all the effort being put in. Equally it doesn't change the work we have to do: make the car faster, and ensure we make no mistakes in any aspect of our work," he explained.

"In Russia the car didn't suddenly gain a lot of performance, rather the team and Kevin in particular were able to extract the maximum and external circumstances also fell our way.

"Not every race will fall for us in this way, but we always want to deliver the maximum possible as well as improving the maximum potential itself."