James DeGale has urged Carl Froch to hang up the gloves and forget about a potential world title fight with him.

Londoner DeGale (20-1, 14 KOs), 29, is in Boston where he fights American Andre Dirrell (24-1, 19 KOs) for the vacant IBF world super-middleweight title on Saturday after spending nine days finishing off his training in Miami.

Froch, who turns 38 in two months, gave up the IBF belt earlier this year and was also stripped of the WBA title last week.

The Nottingham boxer has not fought since knocking out George Groves at Wembley a year ago with speculation mounting he will retire, though he has said he may be tempted to extend his career against the winner of DeGale and Dirrell, whom he out-pointed in 2009.

"I think Froch is finished and he should retire," DeGale told ESPN. "He's getting on, earned a lot of money. He needs to relax, chill and retire. I expect him to retire.

"There's no point in him coming to me, I would absolutely batter him. He would not win a round off me. He's tough and durable but deep down he knows there's a slim chance for him."

Eddie Hearn, who promotes both Froch and DeGale, admits it is looking likely that Froch will announce his retirement soon.

"Marvin Hagler said it is difficult to do your running when you get up in the morning in silk pyjamas," he told ESPN. "It's the same with Froch but when Carl's teak-toughness goes he ain't the same fighter.

"Can you still be the same fighter when you have all that money in the bank, lovely family, two kids and another one on the way, lovely house? DeGale-Froch could become a Wembley fight but he might turn around and say he's a good fighter, I don't need it.

"It's nice to retire rather than get retired, to leave on your terms. As my friend. I would quite like that for him. I would feel job done.

"He hasn't phoned me once since that Wembley fight and said right, what are we doing? I've always gone to him with the Julio Cesar Chavez Jr fight, which fell through, Bernard Hopkins, Gennady Golovkin.

"I love the Golovkin fight but unless HBO come up with a pot full of money, that fight with Golovkin won't happen because he won't do it for a laugh ... a fight with Golovkin is not a laugh."

DeGale will attempt to become Britain's first Olympic gold medallist to win a world title when he fights Dirrell but he is also driven by the goal to become world champion before bitter rival Groves, whom he lost to on points in 2011.

"Of course it means something to beat George Groves to winning a world title," DeGale told ESPN. "That's why I can't let this chance slip.

"I'm too good to get too many chances at titles, people aren't going to fight me for a voluntary defence, so I have to take this opportunity against a good opponent. Tell me who is better than Dirrell, apart from me?

"I'm 100 percent fit. whereas the previous two years I was fighting injured. I can't wait. It has been so long. I'm bored of waiting.

"The Groves rematch is a fight I would like. I've just got to win this world title then I can start calling out the shots. A lot of people talk about Groves and Froch, but I want to fight the best. I want to fight Andre Ward, Arthur Abraham, Gilberto Ramirez and Gennady Golovkin if he moves up because he's a beast.

"Winning over in America will make all the difference to me."