McLaren reveals cause of Alonso crash

McLaren's Fernando Alonso's had a rocky start to pre-season testing, finding himself stranded in the gravel trap just six laps into the days' first session.

Alonso was on course to set the fastest lap of the day when the incident occurred, triggering the sessions' first red flag in the process.

Footage showed the McLaren heading into the final corner as the rear right wheel came loose, pitching car and driver in the kitty litter.

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The MCL33 was hauled back to the McLaren garage where a thorough inspection revealed a wheel nut issue, according to Zak Brown.

"We had a wheel nut issue. We'll get back out here this afternoon," Brown said.

"I know Eric [Boullier, McLaren racing director] will be doing a debrief later today with all of today's activities, so I'll leave him to tell you about today.

"It's what testing is for. I think all teams will have a variety of issues throughout testing. That's exactly what it's for.

"We're going to lose very little time. It's no big deal at all."

Following repairs, McLaren was prepared to resume running with Alonso shortly before the lunch break.

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