Mark O'Hara and Steven Lawless missed for Graham Alexander's side before Liam Kelly gave Motherwell hope by saving from Kevin Nisbet. But Ryan Porteous kept his composure to seal it 4-2.

"For 80 minutes we were excellent and dominant," Ross said. "In fairness to Graham and Motherwell they made changes and threw caution to the wind but we should still manage the game better.

"They obviously take greater momentum and mentality into extra-time. That's the danger but for us it was about re-setting and in fairness we did that. We handled that half-hour okay and we showed character in abundance in the shoot-out.

"We had faith in a lot of players to score. It was actually picking five that was difficult rather than finding five to take them.

"Ryan was one that was adamant that he wanted to take one of the first five. That's him as a character, for a young man he has got a bit about him and technically he is very good so you don't have any concerns about him handling that sort of pressure."

Alexander thought his side were destined to go through after their dramatic fightback.

"I'm gutted for everybody because I thought the players were magnificent," the Motherwell manager said.

"We came with a game plan to frustrate at first, which worked really well, I don't think they had a shot on target in the first half. But we wanted to create a bit more.

"We took a step back after half-time and allowed them to have easy possession in our half and we were punished.

"But the reaction from that point was absolutely amazing. The players showed the character to get on the ball, press from the front and showed what a quality team we could be.

"To come back against such a fantastic team away from home in such a pressure game to equalise and I thought there was only one winner from that point. Unfortunately we just couldn't get that winning goal."

There was controversy surrounding Irvine's goal from close range.

"It was offside, I have seen it back," Alexander said. "What can you do?"

The Well boss had sprung a surprise by including Watt, who has been troubled by a heel injury and missed the past five weeks.

"If it had been a league game we wouldn't have done it because we are safe now," Alexander said. "But it's the cup so it's win or bust.

"Tony only trained on Friday afternoon and that was only light and he put himself forward which was a surprise to me.

"Even if he can't train for a couple of weeks now, it was worth going for it and he really helped us when he came on."