LONDON (Reuters) - Defending champions Hungary suffered their second loss in a row when they were beaten 11-10 by Montenegro on the second day of the men's water polo competition on Tuesday.

Hungary, the most successful country in Olympic water polo and gunning for their fourth consecutive gold in London, showed their quality in the second half but it was not enough to overcome a determined Montenegrin team.

Hungary lost 14-10 to Serbia on Sunday to end a 12-year, 17- game unbeaten run at the Olympics and they are under pressure to progress with three group games left. The top four in the six-team group qualify for the knockout stages.

Two late penalties, one for either side, delighted an early morning crowd packed with Hungarian supporters, in an exciting end to a match in which the Hungarians hit the woodwork twice in the final minute of the game.

(Reporting by Sarah Young, editing by Ed oOsmond)