MANCHESTER, England - Manchester City suffered a rare Champions League defeat at the Etihad Stadium on Tuesday as Bundesliga side Bayer Leverkusen claimed a stunning 2-0 victory to end the hosts' 23-game unbeaten home run in the competition's group or league stage.

The loss spoiled Pep Guardiola's 100th Champions League match as City manager and left the Premier League side provisionally sixth on 10 points after five games. Alejandro Grimaldo and Patrik Schick scored for Leverkusen, who are 13th.

Guardiola rested most of his regular starters for the first half with 10 changes to his team and the risky move backfired.

Leverkusen opens scoring with counter-attack strike

Leverkusen struck in the 23rd minute on the counter-attack when Malik Tillman sent in a cross that Christian Kofane held up in the penalty area for Grimaldo to fire home.

Guardiola sent on reinforcements to start the second half in Phil Foden, Jeremy Doku and Nico O'Reilly, but it did not stop the visitors doubling their lead in the 54th minute with a glancing Schick header over a lunging Nathan Ake and past the outstretched hands of goalkeeper James Trafford.

But while he was in the thick of the action, there were no late-game heroics with Mark Flekken making a brave stop from the big Norwegian's best chance, a one-on-one with the keeper after running onto a through ball from Foden.

"I take full responsibility, still I think the players that started were exceptional players but we missed something needed at the highest level. We now have to fight for the next games," Guardiola said.

"I have to accept it. If we win it (changes) wouldn't be a problem, so I have to accept it that maybe it's a lot, but I think playing every two or three days we need to (make changes) but seeing the result, maybe it's too much."

Leverkusen keeper Flekken produces brilliant saves

City had been keen to make amends for their 2-1 Premier League loss at Newcastle United on Saturday, but it was not to be and Flekken was a big reason why.

The Dutchman also made brilliant saves to deny Ake and Tijjani Reijnders as City peppered the visitors' goal with 20 attempts, including seven on target to Leverkusen's two.

"It's an unbelievable feeling (to win at The Etihad) to be honest," Leverkusen defender Jarell Quansah told TNT Sports. "We needed a lot of character and a lot of fight and grit.

"We know they've got a lot of world-class quality and even the players that started tonight we know they're world-class players playing for their countries as well, so it was always going to be a tough task when they came on. We defended a bit deeper than I would have liked to but glad to get the win."

Leverkusen boss Kasper Hjulmand called it a night to remember.

"We are so happy with this win, but not only the win but the character the team showed," he said. "I have great respect for the players, for the team we are. We are building a team here, and I think this night is a night to remember, and it's fuel to our development.

"Of course we had moments where we needed a little bit of luck and a very good keeper tonight."

City had not lost at home in the Champions League group stage since a shock 2-1 defeat by Lyon in September 2018.