James DeGale says he has been channeling the spirit of Marvin Hagler with trainer Jimmy McDonnell, as he rebuilds after his loss to George Groves.

DeGale lost a highly controversial split decision to bitter rival Groves in May.

The British and Commonwealth titles were up for grabs, as well as both fighters unbeaten records.

Now DeGale is looking to rebound with a European title fight against Piotr Wilczewski .

No date has been confirmed for the clash, but it is likely to go ahead in London in October.

Currently training hard in Loughton, Essex, DeGale admits that he should have jumped on Groves much sooner in their fight - a mistake he won't make again.

"I learnt a lot from it," said the 2008 Olympic gold medallist.

"One of the things I talked to Jimmy about is being more aggressive.

"I shouldn't have allowed the first eight rounds to turn into a sparring session.

"A fighter that Jimmy and I have discussed is Marvin Hagler, and specifically his fight with Tommy Hearns.

"Hagler went to war against straight away, and if I'd have done that against Groves, I would have won the fight, easy.

"I've been working on being more aggressive and cutting down the ring.

"There are so many good things that can come from a loss, and that is one of them.

"You are not going to see a completely different fighter next time I box, but I will be an improved version of the one everybody saw in May."

Tags: James DeGale , George Groves , DeGale vs Groves , DeGale-Groves