Ipswich Town defender Darren O'Dea is facing six weeks on the sidelines after undergoing knee surgery.
The 23-year-old, who is on loan from Celtic, picked up the injury playing for the Republic of Ireland last month.
Town boss Roy Keane told BBC Radio Suffolk: "It's always disappointing for the manager and the supporters, but also for the player.
"He broke down in the warm-up for the Leeds match, it had been ongoing for three or four weeks."
Fellow centre halves Tommy Smith and Damien Delaney will be in contention to take the Irishman's place for the visit of Coventry on Saturday.
Smith, 20, did not travel to play for New Zealand last week because of an ongoing back injury.
Delaney, 29, has yet to make a league start this season after suffering a blood clot in pre-season.
I think the player's got a few options and he's entitled to speak to the other clubs. I'm hoping it might happen in the next day or two
Ipswich boss Roy Keane on a potential loan signing
"Tommy's back is fine, it's a case of resting and I think the last thing Tommy needed was to be sitting on a plane for 24 hours," said Keane.
"We're always quick to criticise international set-ups, but New Zealand have been very good about it and they're well aware of the situation.
"I think Damien's ready, he's been in training with us this week and is in competition with Tommy."
Keane is hoping to add a loan signing to his squad before Saturday's game, revealing he is in talks with a Premier League player who can feature in defence or midfield.
"The gut feeling is it will happen, we've been in discussions with a club the last few days," he said.
"I think the player's got a few options and he's entitled to speak to the other clubs. I'm hoping it might happen in the next day or two."
Bookmark with:
What are these?