DeGale takes swipe at Groves
Johnson is in the veteran stage of his career, but he has a win over Roy Jones to his name and he took Groves to points last weekend.
It was a fight that Groves' promoter Frank Warren feels will propel the super-middleweight towards a world title shot.
DeGale, though, who has had a rivalry with Groves that dates back to their amateur days, was not impressed with the manner of the win.
"Everyone knows we have history and don't like each other," DeGale told Sky Sports' Ringside.
"Johnson is an old man, he is shot to bits. He should have been hung up by his feet and been a punchbag. I would have made Johnson look stupid."
DeGale has won four on the spin since his loss to Groves in 2011 and he is planning on being active in 2013.
He said: "The next move is to stay busy. I have been working on a lot of different things. I have had 15 fights and I am getting there."