Dundee United defender Mark Connolly is set for a long-term lay-off after snapping his cruciate ligament in Wednesday's draw with Motherwell.

The Irishman suffered the injury just moments after Well snatched a last-minute equaliser in the 2-2 Tannadice clash.

But incredibly, the 29-year-old was able to see out the game, not realising he had suffered major damage until he returned to the United dressing room after the full-time whistle.

Manager Micky Mellon confirmed the former Kilmarnock and Crawley defender is now looking at "months" out of action.

"Mark Connolly has picked up a cruciate knee ligament injury against Motherwell the other night," the Terrors boss said.

"It's as severe as cruciate knee ligament knee injuries are. He's going to be out for months.

"It's a huge blow for him and for us – but we just need to look forward now and try to get him back as quickly as we can.

"The problem with these kind of knee ligament injuries – and I hope no-one ever goes through this – seemingly you don't feel anything, so that means it's snapped.

"Sometimes that can happen and it's the adrenalin running through your body and it's only when you start to calm down that you feel there's something not right.

"Thankfully we've got a doctor who is a knee specialist here and he seen it right away at the end of the game.

"Mark came back into the dressing room and said something doesn't feel right.

"It seems he's just gone up for a header and when he's came back down, he's landed on it a wee bit awkwardly. It sort of crunched down with the weight coming down on his knee. But he played on with it.

"He's also ended up with 10 stitches after a head knock. If it wasn't for bad luck he'd have no luck."

It is another bitter blow for Connolly, who is still coming to terms with the death of his father Martin earlier this year.

"Mark has had a tough time lately in his personal life with losing his dad, so this on top of that is hard," added Mellon, whose team round off their campaign away to St Mirren on Sunday.

"But he's a lad of brilliant character and personality and he will fight forward and get back. But it is a tough time right now and he'll need a lot of support.

"We will support him and make sure he gets back."