In a thrilling Champions League showdown on Wednesday, Harry Kane found the net as Bayern Munich edged past Manchester United 4-3. Meanwhile, Jude Bellingham secured a last-minute, heart-stopping victory for Real Madrid, and Arsenal kicked off their campaign with an impressive win. The clash between Bayern, reigning German champions, and a struggling United squad, which harked back to the memorable 1999 final, lived up to its billing as the standout fixture of this season's opening round.

Leroy Sane gave Bayern the lead at the Allianz Arena with a shot that squirmed through the grasp of United goalkeeper Andre Onana, and Jamal Musiala set up Serge Gnabry to make it 2-0 just after the half-hour mark.

Rasmus Hojlund pulled one back early in the second half with his first United goal, but shortly after, Christian Eriksen was penalized for a handball in the box, and Kane blasted in the resulting penalty.

Sane hit the post for the hosts before a crazy finish saw Casemiro reduce the deficit again, substitute Mathys Tel score Bayern's fourth, and Casemiro nod in another at the death to make it 4-3.

"A crazy finish," Kane told British broadcaster TNT Sports after netting his fifth goal in six games for his new club.

"We lost a bit of concentration there in the last five minutes. Thankfully we were able to hold onto the lead.

"Overall it's a really good start to the campaign against a tough side."

Erik ten Hag's United team have now suffered three consecutive defeats in all competitions and lost four of their last five matches.

"After my mistake we lost control of the game. It's a difficult situation for us, for me," said Onana in reference to Bayern's first goal.

Thomas Tuchel's side are already in control of Group A, in which the other game saw Galatasaray come from two goals down to draw 2-2 with FC Copenhagen.

Goals from Mohamed Elyounoussi and Diogo Goncalves had the visitors in control in Istanbul but they then had Elias Jelert sent off and Galatasaray struck twice in the last four minutes of regulation time through Sacha Boey and Tete to earn a point.

In Madrid, Bellingham seized the moment from close quarters, netting a dramatic 94th-minute winner as the 14-time European champions, Real, triumphed over tournament newcomers Union Berlin with a 1-0 victory in Group C.

The English international has made a scintillating start to his tenure at Madrid, showcasing impressive scoring prowess with six goals in six appearances across all competitions for the club.

"He has great qualities, it seems he's got luck too, because the goal is a rebound, but he was there, he arrives from deep, and he's more switched on than others, he's got that quality and he's taking advantage of it," said Real coach Carlo Ancelotti.

Madrid's next game is away to Napoli, who won 2-1 against Braga in Portugal with Sikou Niakate's late own goal giving the Italian team victory.