Novak Djokovic retained his title at the World Tennis Championship exhibition tournament in Abu Dhabi on Saturday by rallying past Nicolas Almagro of Spain 6-7 (4), 6-3, 6-4 in the final.

The top-ranked Serb was expected to dominate after having swept past David Ferrer in straight sets to reach the final, but the 11th-ranked Almagro was no pushover.

Almagro, a late replacement at the tournament for Rafael Nadal, hit back from 3-1 down in the tiebreaker to take the first set.

Djokovic broke to lead 3-1 in the second set en route to leveling the match. The third set was much tighter, with both players holding serve after eight games until Djokovic went up 5-4 and then broke Almagro to clinch victory.