Toro Rosso rookie Alexander Albon will replace under-performing Pierre Gasly as Max Verstappen's Red Bull team mate from the next race in Belgium until the end of the season, the Formula One team said on Monday.
Gasly will go in the other direction, taking British-born Thai driver Albon's seat at the sister team where the 23-year-old Frenchman started out before being promoted at the end of last year.
The Belgian Grand Prix at the Spa-Francorchamps circuit is on Sept. 1 and is the first race after Formula One's August break.
"Red Bull are in the unique position of having four talented Formula One drivers under contract who can be rotated between Aston Martin Red Bull Racing and Toro Rosso," Red Bull said in a statement.
"The team will use the next nine races to evaluate Alex's performance in order to make an informed decision as to who will drive alongside Max in 2020."
Verstappen has won two of 12 races this season and is third overall on 181 points while Gasly, the 2016 GP2 (now F2) champion, has struggled with just 63 points.
To add to his embarrassment, he has been twice lapped by Verstappen.
Red Bull are third in the constructors' standings but need both drivers finishing consistently high up to have a chance of overtaking Ferrari, who are 44 points ahead of them in second place with champions Mercedes far in front.
Team principal Christian Horner expressed his frustration at the most recent race in Hungary in which Verstappen started on pole position and finished second to Mercedes' Lewis Hamilton with Gasly only sixth.
"The start wasn't great, the first lap wasn’t great and we shouldn’t be racing Saubers (the Alfa Romeo cars) and McLarens," he said.
"We need him to be racing Ferraris and Mercedes.
"The problem is he’s not in the mix at all," he added.
Gasly had performed well last year at Toro Rosso and moved up to Red Bull when Australian Daniel Ricciardo decided to move to Renault.
His demotion means Toro Rosso now have two drivers rejected by Red Bull, with Russian Daniil Kvyat also promoted and demoted and then dropped entirely before being given a second chance.
Albon has got himself noticed this season with strong performances. The same age as Gasly, he has scored 16 of Toro Rosso's 43 points from 12 races.