Former Celtic striker Chris Sutton said of Nygren on Sky Sports: “What a strange player. He can go missing in midfield but comes up with goals.”

Just as well given Daizen Maeda is still looking like a shadow of the player who lit up Scottish football last season, January loan signings Tomas Cvancara and Junior Adamu have yet to fully impress and Kelechi Iheanacho has disappeared from view despite his return from injury.

Nygren is not one of the title winners Tierney talked about in Celtic’s squad, but the 24-year-old Sweden midfielder is doing more than most to make sure he gets that league winners’ medal.

Former Celtic midfielder Scott Allan enthused on BBC Radio Scotland’s Sportsound: “The impact substitutes you’ve seen at the weekend, you’ve seen it again tonight with Benjamin Nygren and James Forrest linking up.

“Lovely tee-up from Forrest and Nygren just finishes – we’ve seen that time and time again and he’s had a real impact in this team.”

Indeed, Nygren has found the net three times and provided one assist in his latest four Premiership games – and his 15 goals are more than any other Celtic player in the league this season.

“I know Nygren gives up certain parts of the game, but what he does do is he gets into the box and gets on the end of things,” Allan said.

“I felt his overall play in the game was really good, played some lovely through balls, always looked like he was going to be a threat round about that 18-yard box and he was the difference again tonight.”

His manager was similary enthusiastic.

“He’s doing something that is the most difficult thing in the game – to score goals -and he’s popped up again with what proved to be the winning goal,” O’Neill said.

“Substitutes in recent weeks have made big contributions to us, so that’s important for us.”