New Celtic hero catches Martin O'Neill by surprise with 'big impact' on pitch and behind scenes

The champions looked set to suffer a major setback in the title race after Robbie Muirhead’s penalty had cancelled out Marcelo Saracchi’s first-half strike.

Oxlade-Chamberlain, however, was thrown on after 78 minutes for his debut after completing a short-term deal and found himself in the right place at the right time to curl in the winning goal.

O’Neill admitted he didn’t quite expect the former Arsenal and Liverpool midfielder to perform such dramatic heroics but conceded that it was for that sort of moment of composure that made signing Oxlade-Chamberlain something of a no-brainer.

“He's been a class player, there’s no question about it,” said the Celtic manager. “He’s played for big teams and performed brilliantly. So, I’m just really delighted to have him and getting him onto the field as well too. He turns the game for us which is brilliant.

“I didn’t think he was going to be as dramatic as that in scoring the goal! But I think that he can give us something, no question about that. He’s a really decent player and he gets up to speed with things. He's only done it a couple of days and I couldn't be more pleased with him.

“He's made a big impact, believe it or not, even in the training sessions with the rest of the players, which is always a good sign. I'm just delighted he's in and I think that when he's properly fit, he'll be great for us.

“It was frantic on the pitch and frantic in the dugout as well (when Oxlade-Chamberlain went on). It was a great strike and I was right behind it when I saw it. The minute it left his foot, I thought, ‘this is in’.”

This was Oxlade-Chamberlain’s first competitive match since turning out for Besiktas in May and O’Neill was pleased Celtic were able to get him.

“He’s incredibly modest about his achievements in the game and he wants to do well,” added the manager. “He’s 32 years of age and should be at the peak of his career. He's gone off to Turkey for a couple of years, perhaps no one wanted to take him.

“I don't know that particular scene but he's had a few managers out there and so he's come back. He's come up here and he wants to have a go, which is great.”

Livingston manager Marvin Bartley praised his players for pushing Celtic all the way until that late, late concession.

He said: “First and foremost I have to give my players a lot of credit for how they played. We had to come up with a gameplan which needed a lot of energy to do so and I thought they did that.

“Ultimately we were beaten at the end by a really good goal by a player who has performed at the top level.”