Updated

By Matt Smith

DUBAI (Reuters) - World number two Novak Djokovic overcame a racket-smashing tantrum and a day-long rain delay to retain his Dubai Championships crown by beating Russia's Mikhail Youzhny 7-5 5-7 6-3 on Sunday.

"It's a very mental game," said the Serb. "People don't realize how much tension you have to go through throughout the match. It took a lot of energy for me. Stopping and playing, and coming back and then again stopping the match last night because of the rain."

The players then exchanged further breaks, with Djokovic smashing his racket until it buckled after he double-faulted to put his opponent 5-4 up. Youzhny eventually won the set as the Russian adapted better to the searing afternoon heat, markedly different to Saturday's cool evening.

"The ball travels so fast during the day, it's incredible. It's like ten times faster than during the night. It's much less control during the day, so it's frustrating," Djokovic said.

He again raced into a 3-0 lead in the decider and although Youzhny broke to level at 3-3, the second seed upped his game again. The Russian hit a long forehand to allow Djokovic to serve out the match, the exhausted Serb collapsing to his knees in triumph.

"Today was another good example of how much I believe in myself and how much I fight till the end," added Djokovic, who gained swift revenge for Youzhny's straight sets victory in the semi-finals of the Rotterdam Open earlier this month.

"All the time when I lose I'm disappointed," said the Russian. "Today I try to play aggressive, maybe more aggressive (than) usual if I want to save this match."

(Editing by Justin Palmer)