Coventry manager Mark Robins wrote off his side’s Sky Bet Championship play-off hopes after their 3-0 defeat at relegation-threatened Birmingham.

An own goal by Bobby Thomas in the 12th minute and strikes from Ivan Sunjic and Jay Stansfield condemned the visitors to a third loss in four games.

Coupled with Norwich’s 1-0 win at Preston, it left the Sky Blues in eighth place, eight points adrift of the top six with four games left.

They have an FA Cup semi-final against Manchester United next weekend and next play in the Championship on April 24 when they host Hull.

“We had to pick points up in three out of the four games we have lost and you can’t do that if you are realistically challenging, so it’s massively disappointing,” said Robins.

“We have given ourselves a mountain to climb. We could be 12 points adrift (of the top six) by the time we next play (in the league) and Norwich are too good.

“We didn’t start at all. Initially we had a couple of shots dragged wide, but they were first to the ball in every challenge. Every first contact they seemed to win.

“It looked like a lethargic performance and people made poor choices and it cost us three goals.

“They took the lead from an own goal where we didn’t get close enough to the attacker (Keshi Anderson), then for the second one, (goalkeeper) Brad Collins was unsighted.

“For the third goal we got dragged all over the place because we weren’t talking and that smacks of fatigue.”

The victory was Birmingham’s biggest win since October – and only their second in 11 games – and it moved them out of the relegation zone after Bristol City denied Huddersfield victory at the death.

Blues led when Anderson’s cross hit Thomas and deflected in at the near post.

Sunjic doubled the hosts’ lead with a rasping low drive that caught Collins flat-footed after a corner and Stansfield made it 3-0 when he clipped the ball past Collins following a superb diagonal run behind the defence which was spotted by Tyler Roberts on the left.

The closest Coventry came to scoring came in the 20th minute when Haji Wright’s lob hit the bar after keeper John Ruddy headed away a clearance.

Birmingham interim manager Gary Rowett challenged his side to repeat the performance for the next three games to avoid relegation.

“That was a much better performance and it had a lot more of what we expect and, lo and behold, you get your rewards,” he said.

“You might not find yourself solid defensively, but you find yourself scoring and creating chances.

“Some of the senior lads held the others to account in midweek (after a 1-0 home defeat to Cardiff) and everyone has taken that on board, which is what should happen. I thought we showed it.

“Now we’ve got to replicate that in the last three games.”

Rowett also praised the positive impact of the 26,811 crowd.

“It’s been no coincidence we’ve had five full houses this season and won all five games,” he added.

“If that doesn’t show the power of our fan base, nothing will. They were brilliant – the atmosphere was incredible.

“It was nice to reward that loyalty with a performance that had a similar edge.”

Birmingham gave their Sky Bet Championship survival hopes a huge boost with a 3-0 home win over Coventry which put a major dent in their visitors’ play-off hopes.

An own goal by Bobby Thomas in the 12th minute opened the scoring, Ivan Sunjic made it two three minutes before half-time and Jay Stansfield killed the contest with his 13th of the season.

The result was Blues’ biggest win since October – and only their second success in 11 – and moved them out of the relegation zone after Bristol City denied struggling Huddersfield with a last-gasp leveller.

Coventry’s third defeat in four left the FA Cup semi-finalists six points adrift of the top six with four games to go ahead of their big date at Wembley against Manchester United next weekend.

The Sky Blues threatened first with a firm, low angled drive from Milan van Ewijk that was deflected just wide.

Blues countered with a stabbed effort from Tyler Roberts and then a shot from Koji Miyoshi that brushed the side-netting.

And they soon got their noses in front.

Lee Buchanan’s throw-in on the left was worked to Roberts, who turned the ball inside for Keshi Anderson, whose cross hit Thomas and deflected in at the near post.

The closest Coventry came to scoring came in the 20th minute when Haji Wright hit the bar.

Goalkeeper John Ruddy came out of his box to head away a clearance, but only as far as Wright, whose volleyed lob bounced before hitting the woodwork.

Blues remained in the ascendancy and Stansfield twice should have done better instead of firing first over and then several feet wide from 20 yards.

Sunjic doubled the hosts’ lead with a rasping low drive from just inside the area after Paik Seung-ho’s corner was headed away by Liam Kitching, his effort catching keeper Bradley Collins unawares.

Coventry, following a triple substitution at half-time, began the second half looking much improved, creating two quick opportunities.

Kasey Palmer’s 25-yard drive was parried by Ruddy, then Ben Sheaf fired a rising effort over from just inside the area.

There was now an edge to the match and Stansfield and Van Ewijk were booked for shoving each other after the Blues striker was penalised when he thought he had won the ball back.

But Birmingham dashed any hopes of a Coventry comeback when Stansfield made it 3-0.

The on-loan Fulham forward clipped the ball past Collins after his superb diagonal run behind the defence which took him beyond Kitching was spotted by Roberts.