MANCHESTER, England－Perched high in the stands, Pep Guardiola buried his head and covered his eyes.

At times, the Manchester City manager couldn't bear to watch as his Champions League hopes were extinguished.

On a night when his players needed him most on the touchline, Guardiola was largely helpless to intervene.

The elevated view was not out of choice, but for allowing his emotions to boil over as the players departed for the halftime break.

The target of Guardiola's wrath was Spanish referee Antonio Mateu Lahoz, who had incorrectly ruled out Leory Sane's goal minutes earlier for offside after failing to spot that the ball had come off Liverpool's James Milner.

"I didn't insult the referee," Guardiola said. "I just said, 'It's a goal. It came off Milner.'"

The remonstrations achieved nothing apart from Liverpool Jurgen Klopp having no company on the sideline for the second half of this quarterfinal second leg that City lost 2-1 to go out 5-2 on aggregate.

Had Sane's goal not been disallowed, City would have jumped 2-0 in front on the night.

Trailing 3-0 from the first leg at Anfield last week, a comeback would have seemed not just possible but highly conceivable from the team Klopp hails as "the best in the world".

"We mature constantly," Klopp said after the game in which Liverpool became the first team to beat a Guardiola-managed side three times in one season.

"The boys are getting more and more used to this. If you could say something about us in the past, on an average day we lose cheap goals. We've worked at that," said the German.