"To be fair, they are a fiery bench and we are a fiery bench as well," Johnson said.

"There was a bit of handbags. To be honest, I don't actually know what started it. It's nothing."

Wolves manager Nuno Espirito Santo, meanwhile, said: "Yes, I was aware of it. The referee told us he had a warning."

Wolves booked a first FA Cup quarter-final appearance for 16 years after they ended City's long unbeaten record.

Midfielder Ivan Cavaleiro's first-half finish brought City's 15-match undefeated run and nine-match winning streak to a halt.

The Championship club had their moments, and were far better in the second half, but Wolves deservedly progressed.

Nuno added: "I thought we played really well in the first half, building, creating chances, scoring. The second half, we had to hold on to what we had.

"It is very difficult to defend against such a very good team, and we had to be brave.

"I am very happy because we have achieved something very positive for us. It is a tough stadium to come to and take away something.

"We were the better team in the first half, we created a lot and didn't concede too many chances.

"We are always looking for the best options in a strong XI. There is no such thing as rotation for us, it's always looking for the right options.

"We really appreciate this competition, and we go for it, of course."

City, meanwhile, suffered their first defeat since November, but Johnson took considerable comfort from his side's second-half display.

"We have got to respect that Wolves are a fantastic side, full of energy, power and quality, and I thought we really gave it a go," he said.

"In the first half, we were off the pace in comparison. Tactically, we didn't get our game going, and the second half was the complete opposite.

"We showed character, charisma and identity in the second half. It's hurting that we are out of the cup, because we felt that we had a chance.

"But you have got to learn from defeats, and we take the positives, but we also understand where we are a little bit short at that level. We took a very good side right down to the wire.

"I did think it was handball for the goal.

"I wasn't sure whether we were playing Wolves or the Harlem Globetrotters at one point! There were three hand-balls. The one that (Willy) Boly received from the goalkeeper as well.

"The one that disappointed me was the goal. It was clear. Although it was a ricochet, it laid the ball perfectly into the path of (Matt) Doherty to square it into an area where we didn't have players recovering."

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