The 158th Boat Race had to be halted midway through because of a swimmer in the River Thames.

The Oxford and Cambridge boats were side by side after eight minutes when the sight of a man in the river ahead of them forced them to stop.

It was decided the two boats would return to Chiswick Bridge to restart from a straight section of river.

The last time the race had to be restarted was in 2001 when there was a clash of blades.

"It's not ideal but given those circumstances what could we do?" reserve umpire Matthew Pinsent, speaking from the umpire's barge on the river, told BBC Sport.

"It's a safety issue, someone in the water might be a very serious injury if someone was hit by a rowing boat. Fortunately we spotted him and stopped the race. What could we d? We couldn't possibly have carried on.

"The rules don't allow the umpire to designate a winner if you stopped at that point. You have to cross the finish line."

Oxford are the defending champions, while Cambridge lead overall by 80 victories to 76.

More to follow.

Official crews for the 158th Boat Race

Cambridge: Bow - Moritz Schramm (91.8kg), 2 - Jack Lindeman (94.6kg), 3 - Mike Thorp (91.8kg), 4 - David Nelson (92.8kg), 5 - Alexander Scharp (95.6kg), 6 - Steve Dudek (109.6kg), 7 - Alex Ross (102kg), Stroke - Niles Garratt (92.2kg), Cox - Ed Bosson (55.6kg)

Oxford: Bow - Alexander Woods (77.8kg), 2 - William Zeng (82.4kg), 3 - Kevin Baum (91.6kg), 4 - Hanno Wienhausen (93.6kg), 5 - Karl Hudspith (91.2kg), 6 - Alex Davidson (94.6kg), 7 - Dan Harvey (79.6kg), Stroke - Roel Haen (96.8kg), Cox - Zoe de Toledo (49.6kg)