Instead, the NSW Supreme Court jury today found James Dean-Willcocks, 25, guilty of the manslaughter of Magno Alvarado, 67, on October 10, 2009.

The crown had not accepted Dean-Willcocks' guilty plea to the less serious charge of manslaughter.

He had been out celebrating his 23rd birthday when he assaulted Mr Alvarado at Cronulla and was heard to say: "He's Japanese, he deserves it".

When interviewed by police, Dean-Willcocks said he had no memory of the attack, or of shouting racist obscenities.

Witnesses said the younger man punched Mr Alvarado several times in the head, picked him up off the ground, shook him and threw him back down.

A pharmacologist calculated Dean-Willcocks' alcohol level would have been between 0.165 and 0.355 at the time of the attack.

She told the jury that owing to his age, alcohol tolerance and health, it could have been as high as 0.36 and there was a "very good chance of death at that level".

Justice Peter Garling adjourned sentencing submissions to February 3.