David Ferrer has defeated fellow Spaniard Nicolas Almagro in a gruelling three-set encounter to reach the quarter-finals of the Madrid Open.

After both players each dropped serve twice in the opening set, it was Ferrer who won the tie-break 7-5 with two crucial mini-breaks to Almagro's one.

There was again very little to separate the two competitors in the second, but world number 12 Almagro managed to break down the typically dogged Ferrer and take the set 6-3.

With neither man willing to give anything away in the decider, Ferrer dug in to take the tie-break 10-8.