Red Bull advisor Dr Helmut Marko says the team “had to react” to the poor performances of Pierre Gasly this year.
“Gasly has problems in traffic, he loses places and he can’t overtake,” Marko told Auto Bild.
“So we had to react and give Albon a chance until the end of the season. Gasly takes his place at Toro Rosso and then we see who will be driving next year next to Max.”
The 2019 campaign also marks Red Bull’s first with Honda.
The partnership has so far been successful, with Max Verstappen taking two wins and three further podiums.
“We built a car with too little downforce,” Marko admitted.
“We underestimated the progression of our new engine partner Honda.
“They delivered more power than we thought.”
“That’s why we first wanted to compensate for the missing power with a chassis that is very aerodynamically efficient, but we corrected that.
“In the last races, we were almost equal to Mercedes.” added MArko