Novak Djokovic lost his momentum in the second half of last season and was toppled as the world No. 1 by Andy Murray because his work rate dropped, the Serbian¡¯s former coach Boris Becker said on Wednesday.

Speaking a day after the two terminated their cooperation by mutual consent, German Becker said Djokovic¡¯s need to spend more time with his family had derailed him on the court.

¡°He didn¡¯t spend as much time on the practice court in the last six months as he should have and he knows that,¡± said Becker, who helped Djokovic to six Grand Slam titles after they teamed up in December 2013.