The British fighter currently has his sights set on trying to unify the division with WBO champion Joseph Parker expected to be his next opponent in the spring, but should Joshua remain in possession of his WBA belt, he faces the prospect of a showdown with former title holder Povetkin.
From the opening bell, a pattern emerged with Povetkin being given licence to go onto the front foot as Hammer remained on the defensive in the hope of catching the home fighter on the counter.
Hammer landed with the odd big shot but he never once troubled Povetkin and during the second half of the contest, it became a case of whether Povetkin would be able to stop his opponent.
An early finish never threatened to materialise, but Povetkin is now able to think about a future opportunity to regain his world crown.
The announcement of the scorecards was a formality, with Povetkin getting the verdict by margins of 120-107, 120-108 and 119-108 respectively.