Middlesbrough head coach Aitor Karanka was disappointed that his side failed to score more goals in their 2-0 FA Cup success at Barnsley.
Second half goals from Jelle Vossen and Daniel Ayala gave Boro victory in a third round tie they dominated.
After a suspected gas leak delayed the kick-off for 15 minutes, Boro were forced into an early defensive reshuffle when Rhys Williams – making his first start in nearly a year – was taken off on a stretcher after going down injured in the opening minute.
The visitors were well on top in the first half with Kike, Vossen, Lee Tomlin and Patrick Bamford all going close to scoring.
Vossen found the target three minutes into the second half after pouncing on a loose ball inside the area and slotting a low shot past Ross Turnbull.
Kike threatened to increase Boro’s lead when he headed against the bar from Tomlin’s cross.
Although Boro’s Adam Clayton was sent off in the 77th minute after receiving a second yellow card for a challenge on Leroy Lita, Ayala made sure of the result seven minutes later when he headed home a second goal from Grant Leadbitter’s corner.
Karanka said: “The main thing is to get through though so the work is done.
“It wasn’t easy because when we lost Clayton it was a different game
“I’d have been happier if we’d scored our chances. We have to improve and keep concentrating.
“We had five or six great chances and we had to score them because we could have been four or five up at half-time. If we’d have scored earlier it would have been different, but the job is done.”
Commenting on the injury to Williams, who went off in the opening few minutes after making his first start in almost a year, Karanka said: “The worst thing today is a serious injury to Rhys. I wish him all the best. He’ll have a scan and we will know more.”
On speculation linking him with the managerial vacancy at Newcastle United, Karanka commented: “It is a surprise to me.” Asked if he was committed to Middlesbrough, he said: “120 per cent.”
Barnsley manager – and former Hartlepool United boss – Danny Wilson said: “Of course I’m disappointed. We’d set a certain game-plan up to frustrate them because they’re a very good side.
“They had some chances in the first half and there were a couple of good saves from Ross (Turnbull), but we did stifle them.
“In the second half, the disappointing thing from my point of view is that the two goals we did concede were sloppy.
“I thought at 1-0 we were still in the game and then we conceded, which killed us off, really.”