Sharp-eyed observers have questioned rookie Yuki Tsunoda's pace in the pre-season Bahrain test.
Alpha Tauri's young Japanese ended with the second fastest time behind sister team Red Bull's Max Verstappen.
"He delivered a sensational performance," said Red Bull's Dr Helmut Marko. "I expect a heated fight in the midfield."
However, tongue-in-cheek McLaren driver Lando Norris wrote on a post on Tsunoda's Instagram account: "How's the DRS?"
Indeed, keen-eyed observers have noticed that Tsunoda, 20, was activating his DRS some 100-200 metres before the actual DRS zones in Bahrain.
