Teenage Bayern Munich striker Mathys Tel struck late as his side came from behind to beat FC Copenhagen 2-1 in their Champions League clash in the Danish capital on Tuesday.

Bayern lacked fluidity and struggled against an impressive Copenhagen side, who grabbed the lead early in the second half thanks to Lukas Lerager's opener.

With Bayern in danger of losing their first Champions League group stage match since September 2017, Thomas Tuchel's men upped the ante, Jamal Musiala equalising with a superb solo effort.

Tel, brought on in the 77th minute alongside Thomas Mueller with just seven minutes remaining, collected the ball from the Bayern veteran before unleashing a winner past the helpless home goalkeeper Kamil Grabara.

Super-sub Tel has now scored five of his six goals after coming off the bench and ensured Bayern won their 15th group stage match in a row.

Tuchel told Amazon Prime he had been trying to replace Musiala when the forward scored the equaliser.

"He's returning from a muscle injury and we'd tried to take him off," Tuchel said with a smile.

Bayern captain Joshua Kimmich thanked Mueller and Tel, who came off the bench to combine for the winner. "We've got great quality on the bench and they've saved us often this season."

- Bayern full strength -

Injury-hit Bayern came into the match with only two recognised centre-backs and had spent the week courting former defender Jerome Boateng, 35, in the hopes of securing a short-term deal.

Even with a full contingent, Bayern had been worryingly leaky in defence in recent weeks, with 10 goals they have conceded in the past four matches too many for a side who spent big in the summer hoping for a seventh European title this season.

Despite Tuchel's frequent complaints of a "thin" squad, he named a full strength side including star striker Harry Kane, speaking before the match of his "great respect for every Champions League opponent".

The first half went by largely without incident, Bayern again struggling to find fluidity against an opponent willing to press hard and fight as they did in Saturday's 2-2 draw at RB Leipzig.

While the German champions were able to rebound immediately in that match to overcome a two-goal deficit to draw, Copenhagen drew first blood, taking the lead 10 minutes into the second half.

Bayern's Kim Min-jae blocked a powerful shot from winger Viktor Claesson, but the ball fell to Lerager, who crashed in a first-time shot.

The shellshocked visitors looked to get back in the game immediately and dominated possession, but Copenhagen fought hard, wanting to avoid again dropping points from a winning position as they had done while 2-0 up at Galatasaray to draw in their opening game.

With just over 20 minutes remaining, Musiala took it upon himself to drag Bayern back into the game, shedding two defenders while holding a third at bay to slam home past Grabara.

As he has done several times this season, Tuchel turned to Tel and the 18-year-old striker delivered almost immediately, scoring a stunner just six minutes after coming on to give Bayern the lead.

With less than a minute remaining, Bayern 'keeper Sven Ulreich got his fingertips to a loose ball from a cross, helping the club keep their stellar group stage record intact.