Malky Mackay revealed the Scottish midfielder had suffered the blow which could keep him out for three weeks ahead of the Easter double-header against Middlesbrough and Derby.
Latics are currently five points adrift of safety with seven games remaining.
“Don took a nasty fall in training and is maybe going to be out for two or three weeks,” Mackay told the Wigan Evening Post.
“It’s just one of those things, the way he fell.
“We’ve had him scanned and unfortunately there’s bone bruising there.”
Wigan do at least have top scorer James McClean available this Friday following his two-game suspension.
Meanwhile, six academy products have been offered professional deals at the DW Stadium for next season.
Louis Robles, who has been on Latics’ senior bench on numerous occasions this season, heads the list of half-a-dozen players which also includes Sam Cosgrove, Liam Langford, Adam Anson, Adrian Purzycki and Owen Evans.
“This is always such an exciting time, because these lads can be the future of the football club,” academy manager Gregor Rioch told the club’s official website.
“We have made huge strides over the past seasons and the current crop have set such high standards.
“I want to congratulate each and every one of them for their outstanding commitment during their time at the club, they have all shown the desire and talent we look for at Wigan Athletic and I am really so pleased for them.
“They now have an outstanding opportunity to make that next step in their career.”