VIDEO: Verstappen's rear wing jumping up and down

It was a special sight during the last free practice in Bahrain: the rear wing of Max Verstappen went up and down repeatedly. In the end little seems to be going on for Red Bull and Verstappen.

The Dutchman closed the session successfully by setting the fastest time. During the session, however, something remarkable happened. While Verstappen had his DRS fully open during a fast lap, his rear wing suddenly started to flap up and down. So quickly the mechanics didn't know what was going on and told him not to use his DRS anymore. With hindsight, the damage did not seem too bad.