Callum McGregor’s substitution in the second half against St Mirren raised questions, but Martin O’Neill moved quickly to clarify the situation after the match.

The Celtic captain started the game and played his part in the opening goal, with his shot leading to Alex Oxlade-Chamberlain’s finish. He looked involved early on, helping Celtic move the ball through midfield.

Celtic
5th April 2026; Dens Park, Dundee, Scotland; Scottish Premiership Football, Dundee versus Celtic; Callum McGregor of Celtic applauds the Celtic fans

However, he was taken off as the game wore on, with the tempo dropping and St Mirren gaining more control. Given his importance to how Celtic play, any issue around McGregor draws attention.

O’Neill confirmed the midfielder had been dealing with a problem in the lead-up to the match, but made it clear the decision to play came from the player himself.

He said: (TCW), “Callum McGregor, he had a bit of a problem during the week but wanted to play. I’m delighted that he did and really didn’t feel any worse than before.

“I’m absolutely delighted that he got through as much as he did, so we need him. And a few others, but we stayed strong.

“Well I’m not so sure. I think now a few days off for him, I think he’ll be ready.

“I think psychologically, playing the game today was big news for him. Not that we were saving anybody for a semi-final, not at all.

“That’s there, that’s in the next eight days or something. We weren’t saving anybody. He wanted to play, he wanted to start the game and he felt okay to start it. So that’s good and I don’t think he’s done any harm.”

McGregor’s role in this side is clear. He sets the tempo and keeps the ball moving, especially in games where Celtic need to break down a defensive shape.

When he came off, that control dropped. The passing slowed, and Celtic struggled to keep St Mirren pinned back in the same way.

The positive for O’Neill is that the issue does not look long term. A few days of recovery should be enough, which keeps him in line for the next run of games.

Celtic FC Martin O'Neill

With a semi-final coming up and the league still tight, having McGregor available matters. Celtic rely on him to keep structure in midfield, especially when games become stretched.

His willingness to play through the issue also says a lot. In this stage of the season, that kind of presence on the pitch can make a difference when matches start to drift.