Barnsley manager Mark Robins was unhappy at the circumstances surrounding Norwich's equaliser in the Tykes' 2-1 defeat at Carrow Road.
Barnsley snatched the lead against the run of play in first-half stoppage time when summer signing Jay McEveley headed in Kieran Trippier's free-kick.
But the 63rd-minute introduction of substitute Anthony McNamee turned the game in Norwich's favour. Within eight minutes his cross was turned into his own net by Stephen Foster before the winger played his part in the winner 10 minutes from time.
His delivery caused havoc in the Barnsley defence before Adam Drury found Chris Martin, who made no mistake from 12 yards for his first league goal of the season
He said: "It's extremely frustrating because their equaliser came when Jason Shackell was off the pitch. The referee told him he had to go off to get treatment for an injury, when he wanted to stay on because we had a free-kick to defend. It was an absolutely pivotal moment in the game because before that I thought we looked comfortable and were controlling the game.
"We had some great chances to stretch our lead but unfortunately we didn't take them and then that happened."