Michael Stewart feels Yosuke Ideguchi was lucky to avoid a broken leg as he branded Mouhamed Niang's tackle indefensible.
The Alloa man caught the Celtic midfielder high with a raised boot in the second half of their Scottish Cup tie, forcing the Japanese international off with an injury.
Manager Ange Postecoglou offered hope after the match that his new signing won't face too long on the sidelines as he refused to be drawn on whether a red card should have been shown.
But in the studio Stewart did not hold back after the match as he watched replays of Niang's challenge, which earned him only a yellow card.
And the former Hearts midfielder felt the Celtic man was lucky to be able to walk away from the incident.
Stewart said on Premier Sports: "It's the sort of tackle that when you see it happen in real time it's an old school crunching tackle.
"But when you see that replay he catches him right above the ankle.
"I don't think you can defend that, you just can't. That's a leg-breaker and hopefully Ideguchi is OK.
"So, yes, to answer your question it's not just a straightforward, old school, hard tackle. It's a bad tackle and could easily have got more than that."
