BURNLEY manager Sean Dyche fears Johann Berg Gudmundsson is facing a lengthy spell on the sidelines, and slammed the challenge that caused the injury as a red-card offence.

The Clarets' Carabao Cup second round penalty shoot-out win over the Blades came at a price as winger Gudmundsson was given oxygen before being carried off on a stretcher after a horror challenge by Jack Robinson.

The defender won the race for the ball, but the heavy tackle came from behind, and the follow through caught the Iceland international knee high and knocked him off his feet.

It was a cruel blow for Gudmundsson, who had opted out of international duty for the recent Nations League games so that he could focus on his fitness for a new Premier League campaign after an injury-hit season.

But Burnley's first competitive game of 2020/21 came to an abrupt halt for the 29-year-old inside the first 15 minutes, with the squad already down to the bare bones.

"I didn't see it back until half-time to be fair. At the moment of asking our players thought it was a bad one - I didn't think it was a bad one. I told Chris (Wilder) 'in my day, in your day, that was standard'. But having seen it back at half-time it was a really bad challenge and he should have been red-carded," said Dyche.

"It's a twist of his knee, and I think it's unlikely at this early stage it will be a matter of days, I'd be very surprised.

"We'll wait and see, he's settled down a bit now, but we'll have to give him 24 hours and make a decision on what the next steps are.

"He's been looking nice and sharp and it's another player down and we haven't got a lot in the pipeline to my knowledge, so it's not helpful.

"You lose a very good player, who's had a tough time with injuries and was looking really fit and well, to a needless challenge."

Dyche also questioned why the incident had gone unpunished by referee Paul Tierney, with the VAR system not in use for this fixture.

"I was amazed by some of the decisions tonight, it seems to be when VAR goes away, how does that work then?" he said.

"No crowds of course in the stadium, so that affects them. They're human beings, I get that, without that pressure of a crowd sometimes it changes things.

"But it was clear for the linesman. He's five yards away, the referee maybe different, the fourth official can see from where I am it doesn't look a good challenge."

Of winning the tie, which sets up a trip to Millwall in the next round, Dyche added: "I thought the players were excellent, they arguably did enough to take the game before penalties."