Red Bull junior Pierre Gasly replaces Daniil Kvyat at Toro Rosso for Malaysia

Red Bull junior and 2016 GP2 champion Pierre Gasly will replace Daniil Kvyat at Toro Rosso for the Malaysian Grand Prix as part of a multi-race evaluation for a drive next year.

Gasly has been driving in Japan's Super Formula this season having failed to secure himself a spot at Toro Rosso for 2017 and is in contention for that series' title. Having tested for senior team Red Bull at tests in Bahrain and Hungary earlier this year, the Frenchman will now get a chance to show his credentials across a race weekend.

Tuesday's announcement stressed that Kvyat remains part of the Red Bull family but that frustrations at his poor form this year prompted the decision. It also stated the Russian will be rested for "the next races", suggesting Gasly will remain in the seat for the Japanese Grand Prix one week later.

With the U.S. Grand Prix clashing with the final race of the Super Formula season, Kvyat looks likely to return in Austin.

Originally it appeared as though Gasly would get a chance at Toro Rosso if Carlos Sainz made an early switch to Renault, the team he will join in 2018. However, with Jolyon Palmer refusing to accept Renault's pay-out, it appears as though Sainz will see out the season with the Faenza squad.

Toro Rosso boss Franz Tost says the team has made the switch in order to make "an informed decision" about next year's driver line-up.

"Scuderia Toro Rosso was established by Red Bull to bring youngsters from its Junior Programme into Formula One and that's what we are doing by giving Pierre this chance," Tost said. "He is the next in line at Red Bull for this opportunity and he has shown that he deserves it, having taken the 2016 GP2 title and this year being very competitive in the Super Formula series in Japan. He really has a valid chance of winning the title, as he is only half a point behind the leader.

"The driver switch gives us an opportunity to make a more informed decision regarding our 2018 driver choices. For a variety of reasons, some of them due to technical problems, but others being mistakes of his own making, Daniil Kvyat has not really shown his true potential so far this year, which is why we are standing him down for the next races. This will give us the opportunity to evaluate Pierre on track during a proper race weekend."

Malaysia will be Gasly's F1 debut and the Frenchman is relishing the opportunity to prove he is worthy of a full-time drive.

"I would like to thank everyone who has helped me get this chance in my motor racing career and specifically, Red Bull, Dr. Helmut Marko and Scuderia Toro Rosso...this is a great opportunity for me. I feel as ready as I can be, having had to be prepared for anything in my role as Red Bull Racing's third driver this year. I will do my best to perform well with Scuderia Toro Rosso during these coming races."

Gasly has chosen the number 10 to accompany him on his car throughout his F1 career.

For Kvyat, the move comes at the tail-end of a frustrating campaign so far. The Russian has scored just four points compared to Sainz's 48, though the Spaniard's recently-announced 2018 switch to Renault appeared to have given Kvyat a better chance of staying put next season.

Kvyat started his career at Toro Rosso in 2014 and earned a promotion to Red Bull to replace Ferrari-bound Sebastian Vettel the following season. However, he struggled to live up to expectations at the senior team and was demoted back to Toro Rosso for Max Verstappen ahead of the 2016 Spanish Grand Prix.