Alex Albon will take Pierre Gasly's drive at Red Bull for the second half of the 2019 season, with Gasly moving back to Toro Rosso.
Gasly joined Red Bull from Toro Rosso at the start of the year but has struggled for performance, scoring just 63 points to teammate Max Verstappen's 181. Meanwhile, Albon has impressed in his debut season in F1, scoring 16 points for Red Bull's junior team Toro Rosso.
In a statement on Monday, Red Bull confirmed the two drivers would swap teams.
"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," the statement said.