MANAMA, Feb 21 — Triple world champion Max Verstappen made sure it was business as usual, despite uncertainty surrounding his Red Bull team boss Christian Horner, by leading the way as Formula One began pre-season testing in Bahrain on Wednesday.

The 26-year-old Dutch driver, winner of a record 19 of 22 races last season, was top of the morning session with a lap quicker than the fastest effort on the first day at the same Sakhir circuit last year.