Derby manager Frank Lampard was left frustrated as his Rams side slipped out of the play-off places following their 2-1 defeat at Stoke.
The hosts went in front through Sam Clucas on 25 minutes, but saw Peter Etebo dismissed by referee Darren England before the break for a rash challenge on Richard Keogh.
During the coming together between the two sets of players, Derby midfielder Bradley Johnson appeared to have the shirt of Stoke’s Joe Allen in his mouth.
Derby were back on level terms five minutes after the restart when Harry Wilson curled a free-kick beyond Jack Butland prior to Tom Ince winning an action-packed, ill-tempered Championship clash, and giving Gary Rowett the victory against his former club.
Lampard felt that the game was there for the taking when Stoke went down to 10 men, with Derby also losing Curtis Davies to an Achilles injury before half-time, with the defender stretchered off.
He said: “We are disappointed to lose a game against 10 men when you get yourself at 1-1. From there it is ours to win. The mistake gives them the second goal, then it is a difficult situation to break down 10 men behind the ball, so we’re disappointed.
“We could have done more in the last half an hour to get back and at least draw the game.
“Joe Allen and Gary Rowett just said there wasn’t much in it (the alleged incident), I haven’t seen it again, so I can’t give any information other than that.”
Stoke boss Rowett was proud of his team to overcome his former side with 10 men.
Rowett said: “I thought in very difficult circumstances over the course of the 93 minutes we were absolutely brilliant tonight and I’m proud.
“When we had the sending off, I felt dejected, but we settled down.
“Originally someone said to me Bradley Johnson’s bit Joe Allen, I’ve spoke to Joe Allen, he’s said nothing problematic, and the referee. We certainly won’t be pushing for anything and I hope no-one else does.”