Brennan was injured during their 1-0 win away to Galway United last Friday night
Drogheda United will be without Killian Brennan for between eight and 10 weeks after suffering a broken collarbone last Friday night in Galway.
The Premier Division side got their top flight campaign off to a winning start with a 1-0 win away to the Tribesmen at Eamonn Deacy Park, but will be without the services of the former Shamrock Rovers man for the forseeable future.
The club confirmed the news to Newstalk.com on Tuesday afternoon.
Brennan was replaced by Robert Thornton and the visitors went on to win the game thanks to substitute Gareth McCaffrey's late goal.
His absence will be a big blow to the Drogs, as Mick Cooke explained to Newstalk.com last week: "Killian is one of the best players in Ireland for the last 10 years," he said.
"My worry about Killian is when you saw him in league winning teams, whether it be Rovers or with Pats... it's his attitude when things are going wrong. And his attitude with senior players, he got on their nerves. So what's his attitude going to be like with younger players?
"I just hope Killian can rein in his temperament and help these younger players rather than get on their backs. It's a big step up for them. They have a lot of players with very little Premier Division experience."