Oxford held a slight advantage heading into the final bend when umpire John Garrett called a halt to the race after the swimmer narrowly avoided being hit by the blades from the Dark Blue boat.

The race was eventually restarted at the half-way point after a 31-minute delay.

Oxford pulled half a length clear when a clash left six man Dr Hanno Wienhausen with a broken oar.

At that point the race was effectively over and Cambridge pulled clear to win.

Umpire Garrett warned Oxford cox Zoe de Toledo to move across just before the clash.

De Toledo argued the wash in the River Thames was too strong for her to move fast enough but her appeal was rejected.

Oxford bow man Alex Wood, 27, was carried off the Dark Blue boat and given medical treatment after the finish line.

The swimmer who caused the race to be delayed has been arrested on suspicion of a public order offence and is being held in custody at a west London police station while inquiries are carried out, Scotland Yard said.