JOE Riley is likely to miss the whole of City’s season with a serious knee injury he suffered in training.

The former Manchester United defender is set to undergo an operation tonight to repair his damaged cruciate ligament.

But Gary Bowyer expects Riley to be out long term – and struggling to play again in this campaign.

He said: “It’s a massive blow to the lad, first and foremost, and then obviously to the club as well.

“The poor lad was devastated (when it happened) last Thursday. But he came back in the following day with an incredible attitude to have a real good go at it and get himself back as quickly as he possibly can.

“It was just an innocuous slip in training. There was nobody near him and we’re really disappointed.

“We wish him the best of recoveries knowing that we will support him with the medical team we’ve got.”

Riley had hoped to rebuild his City career after a difficult first season at Valley Parade which saw him sidelined by former boss David Hopkin.

The full back started just six games and was not involved in the squad after October, with Hopkin looking to move him on during the January transfer window.

But Bowyer stressed it was a clean slate going into pre-season and Riley caught the eye with decent displays in the friendlies.

Bowyer added: “The way he had performed in pre-season had put him into contention like everybody else.

“Unfortunately, we can’t call on him now but you’ve got to think about the boy being out injured and what he’s facing on the road to recovery.

“We’ll try and help him. We’ve talked about him maybe going to watch games when he’s had his operation and wants to help out.

“He’s fine that so we’ll keep him involved and keep his spirits up. That’s our main aim now.

“Initially, he was devastated and it’s a great show of his mental strength that he was determined to get himself in the best possible nick before the operation.

"That will obviously help him with the speed of his recovery."

Luca Colville, who is still on a week-to-week deal, has not been able to train through illness.