Christian Horner revealed he was blindsided by Max Verstappen's antics at the Hungarian Grand Prix, which may have affected his performance levels.
Verstappen cut a frustrated figure throughout Sunday's race, and could only finish down in fifth position having been challenging for the lead at the start of the race.
Verstappen could not get past Hamilton throughout the race, and resorted to a late move down the inside of the seven-time champion which resulted in the pair touching wheels and Verstappen's car being flung into the air.
Verstappen up late before Hungarian GP disaster
Earlier in the race, Verstappen's stress levels inside his cockpit had already begun to rise, with the Dutchman taking issue with engineer Gianpiero Lambiase at various points of the race, including telling him Red Bull had given him a 's***' strategy.
Lambiase proceded to call the Dutchman 'childish' when Verstappen had told his Red Bull team to alert the stewards about Hamilton's driving, after the three-time champion had made his desperate dive down the inside of the Mercedes man.
Verstappen's grouchiness throughout the race continued in the media pen, when he refused to take responsibility for the incident in his post-race interview.
Before the race, Formula 1 champion Nico Rosberg revealed on Sky Sports F1 that Verstappen had been up until 3am on Saturday night taking part in the 24 Hours of Spa sim racing event.
When asked before the race whether Verstappen's lack of sleep may cause a blip in performance levels, Verstappen's team principal Horner told Sky Germany: "That's the first time I've heard that.
"Max knows what his job is here. He is completely focused. This morning during the briefing he was completely awake, very clear."