St Johnstone 2-5 Celtic: Penalty calls upset Tommy Wright
Tommy Wright felt St Johnstone were denied two penalties against Celtic and was upset at the award of a spot-kick for Brendan Rodgers' team, who won 5-2.
Trailing 2-1, Celtic were controversially given a penalty for handball against Keith Watson.
And manager Wright says infringements on Saints' Danny Swanson and Joe Shaughnessy in the box went unpunished.
"My players have done their job, Celtic have done their job, but unfortunately the officials haven't," he said.
"We actually should've had two penalties, if we're going to be honest.
"Danny's is a penalty. I've seen it back, thought it was at the time. It was a penalty.
"When a player contacts a player, makes no contact on the ball in the box, it's a penalty.
"You can quite clearly see his left knee gets pushed in, so there was contact [from Scott Brown] and that should've been a penalty.
"Joe Shaughnessy's dragged to the ground when the ball's in flight. The referee blows his whistle, warns the Celtic player. That should've been a penalty.
"And their penalty, if I live to 100, should never be a penalty. Absolutely, it should never be a penalty. I don't know how he can give it. I genuinely don't know how he can give it. I don't.
"I've been able to shout on to him [referee Craig Thomson] on the pitch and he puts his hands up to me as if he's caught the ball and it hasn't. It's hit his hip and probably touched his elbow. You can see that on the replay.
"You couldn't be sure. To give a penalty, you've got to be 100% and that'll be his answer with Danny's one, but certainly not with that [penalty awarded against Watson]. That cannot, should not happen at this level of football."
After substitute Moussa Dembele converted the spot-kick, the French striker scored again and completed his hat-trick after Scott Sinclair had fired Celtic's fourth goal.
Earlier, Liam Henderson had put Celtic ahead, but Watson's header and an own goal by Dedryck Boyata turned the match temporarily in Saints' favour.
"Granted, Celtic could go on and win the game 3-2, 4-2 without that decision because they've got so much talent and they bring on a striker [Dembele] reputedly valued at £40m, a quality player, and what they've got on their bench and what they had on the pitch," Wright told BBC Scotland.
"They had started the second half well, we had weathered that storm and the game was quietening down again, which was suiting us.
"The decision ultimately changes the whole dynamics of the game, gives Celtic a lift. It shouldn't deflate us a little bit, but it probably does. The players are angry and ultimately that is a game changer.
"We did look a real threat. With the ball, we were slightly better than what we had been against them."
Asked if he was going to speak to referee Thomson, Wright replied: "No, I'll be consistent, I'm not going in because I don't really see the point."
Rodgers had sympathy for his fellow manager and Northern Irish compatriot.
"If I'm Tommy then you're obviously bitterly disappointed," he said.
"You're 2-1 up. If they can keep hanging in there and hanging in then you never know what can happen.
"We get that wee rub of the green. We've had other moments when we haven't had it, but if I'm Tommy, I'm disappointed.
"For us, I'm happy to take it. Great penalty by Moussa and he's only on the field, but then after that we're really fast and clinical in our game."
Celtic's fifth goal came when Mikael Lustig's rabona trick found Callum McGregor, who in turn back-heeled for Dembele to score.
"The last goal was sensational," added Rodgers. "Mika from right-back's had about six or seven one-twos and great bit of skill, so that shows you the confidence, where the players are at."