Craig Levein reckons Reo Hatate "got away with murder" after he avoided a red card against Dundee United.
And Chris Sutton believes the midfielder was "slightly fortunate" to stay on the pitch.
The Celtic midfielder went in late on Kieran Freeman and the home players were furious with the challenge.
Replays showed he went in with his studs up and caught the full-back but referee John Beaton only brandished a yellow card.
And former Tannadice boss Levein reckons he was lucky to get away with it - hinting that the referee was more lenient on Hatate because he wasn't a defender.
Levein said on Sportsound: "I think that could be a red card. I wouldn't be happy with that, I've just seen the replay on the TV.
"Sometimes those attacking players get away with murder.
"If that's a centre-back he's probably pulling out the red card."
Meanwhile, Sutton reckons Celtic were never in any real danger at Tannadice as an early opener from Callum McGregor set the tone before Giorgos Giakoumakis got a double.
"You know what, Dundee United gave it a go at the start of the second-half," Sutton said on Premier Sports.
"Celtic weathered the storm then it's a poor error from Siegrist for the second, and then they really strolled it.
"They made substitutions towards the end of the game and were never under any real threat from Dundee United."
And co-pundit Michael Stewart agreed, insisting Dundee United failed to really put Celtic under serious stress.
He said: "Not really, at all. Chris makes the point Dundee United made a better fist of it at the start of the second half but they still never put Joe Hart under any threat.
"From Celtic's perspective that was a calm and controlled performance, even when United were getting into it a bit more.
"Callum McGregor, for me, was a standout, really composed in the middle of the park and Giakoumakis came up with couple of goals.
"If you remember the cup tie with Alloa earlier in the season, he spoke about goals being like oxygen for him.
"He suffered in the first half of the season from not being able to get a run but he's starting to put a few goals on the scoresheet now."
