"It's a really poor decision," wrapped O'Neill.

"I've watched it back and I didn't believe it was a red card at the time. It was the assistant who notified the referee, we can tell that from hearing his shout.

"What's happened really is there's a coming together and our centre-back has tried to block his run a little bit and the Barnsley player has thrown himself to the ground holding his face.

"The assistant has deemed that a red card, but it's disappointing that the player would do that.

"And secondly disappointing that it was given because it was a really poor decision.

"We have footage from our own analysts, so we're looking at what our options are for an appeal tomorrow.

"However, the players deserve enormous credit for the injustice of the decision and then to come back to make sure we took something from the game."

Stoke rode their luck at times but Smith's first goal since March 2017 made sure of a point.

"When we lost the first goal, which was a poor goal for us to concede, we started to get a grip on the game," admitted O'Neill.

"We knew Barnsley would come and press us, but we still tried to continue and build the game from the back which was a positive.

"Our final ball was a little bit weak at times, but our reaction to losing the goal was good.

"But the most concerning thing is the second goal. We just switched off.

"We didn't defend well on two or three occasions where we should have been tighter. Ultimately, we go in 2-1 down – and that should have never been the case.

"But we got ourselves level again and I think we were in a strong position to go on and win the game until, obviously, the red card.

"We haven't looked like conceding goals like that this season, it was out of character. We were too open at times and missed tackles at key moments."

Frustrated Barnsley caretaker boss Adam Murray admitted his side missed a trick as they remain winless in the Championship so far this term.

"It's more frustration than anything that we haven't come away with a win," admitted Murray.

"I thought overall the performance was very good. I think we were in control for a lot of the game, I thought we had a game-plan which worked.

"We scored two very good goals. We've got a squad of players who can score goals, especially in those forward areas.

"We've spoken a lot over the last couple of weeks about getting into better areas and turning chances into very good chances. I think we did that tonight.

"But unfortunately in the last 20 minutes we were just lacking that finishing touch. It's frustrating."

Goalkeeper Jack Walton spilled a routine cross to gift Smith Stoke's second equaliser, but Murray stressed: "It's one of those things. Goalkeepers make errors and they always get punished, but we won't speak about it again.

"Jack's obviously frustrated, but if it wasn't for Jack I don't think we'd still be in the Championship. We move on."