Red Bull team principal Christian Horner is hopeful there will be no further issues for Max Verstappen after a gearbox failure in the first free practice session at Zandvoort.

The championship leader is seeking to win back-to-back races at his home Dutch Grand Prix this week but his preparations suffered a significant hit when he stopped in a plume of smoke on Friday.

Verstappen stated over team radio that it was a gearbox issue, leading to concerns ahead of Sunday's race, but Horner is hoping the reigning world champion would be able to participate in the second practice session.

"We lost drive once he took a shift from four to fifth, we need to get the car back, understand that and hopefully get it turned around quickly for the next session," he explained.

With Verstappen leading the championship battle by 93 points ahead of team-mate Sergio Perez, with Charles Leclerc a further five behind, the title race is widely considered to be wrapped up, but Horner warned there is still time for things to change.

"Still eight races to go including a sprint race. Anything can happen. We've just got to keep our heads down, keep doing what we've been doing and the championship tables will take care of themselves," he added.

"Spa was probably the most dominant win we've ever had, it's difficult to understand what was it, did they take a step back, did we take a step forward? Max was in a league of his own."