Celtic manager Neil Lennon hailed the "outstanding" Kristoffer Ajer after the Norwegian scored his first goal in Scottish football.
Ajer lined up at right-back at Fir Park and netted Celtic's quickfire equaliser in their 5-2 Ladbrokes Premiership win over Motherwell.
The centre-back was filling in for Hatem Abd Elhamed, who was given the day off to recover from a minor muscular problem ahead of Celtic's Champions League second leg against Cluj on Tuesday.
But he looked more than comfortable in the position as he defended superbly as well as racing forward to reach a return pass from James Forrest and cancel out Liam Donnelly's opener.
Celtic went on to dominate after Leigh Griffiths netted from a free-kick just before the interval and Forrest, Odsonne Edouard and Ryan Christie were all on target before Donnelly's late consolation.
Lennon said: "Ajer was magnificent. He is playing so consistently, I don't think he has missed a minute of a game for me, certainly in the league anyway.
"In Sarajevo he played right-back, was brilliant, and he was brilliant again. It's not an ideal scenario, having to change the back four from Wednesday.
"But it shows the quality he has, he is not just a versatile player, he plays the positions really, really well. He doesn't just get by, he is outstanding in both of those positions at the minute."
Griffiths hailed the potential of Ajer and the 21-year-old's finishing prowess.
"You saw big Kris Ajer strolling up from right-back, it was like he was a big Duncan Ferguson up there, such a composed finish," the striker said.
"The sky's the limit for him, honestly. He can play centre-half and right-back, he is so composed, so good, for such a young lad as well.
"The world is at his feet, he can go all the way as long as he keeps his feet on the ground. He was absolutely different class, didn't put a foot wrong."
When asked if he drew comparisons with a young Virgil Van Dijk, Griffiths said: "Yeah but I don't think Virgil would have been happy to play right-back whereas you saw the big man strolling up there, it was like four or five strides and he is in the the penalty box.
"He is so athletic and so fit. He can play right-back and it doesn't bother him a bit."
Motherwell took the game to Celtic and impressed in the first half, with midfield three Donnelly, Allan Campbell and Liam Polworth causing Celtic problems.
But the hosts could not maintain their efforts after the break.
Manager Stephen Robinson said: "We need to take the individual errors out and continue to build on what we are doing.
"At the minute our wide players don't have the fitness levels to go for 60-90 minutes. We have to get over that barrier and get them through that without getting injured. But there's a lot of positives I can take."