Rafael Nadal has beaten Tomas Berdych in three sets at the ATP World Tour Finals to progress to the last four of the tournament unbeaten.
The world number one got off to a fast start in his final round robin match, breaking the Czech player in the opening game, which was enough to hand him the first set.
Berdych upped his game with some powerful serving in the second set to get himself back into the tie, breaking the Spaniard twice to take a 5-0 lead before serving out the set 6-1.
The pair looked well-matched at the start of the deciding set as the first seven games went with serve, but Nadal got a break at a crucial point, setting himself up to serve out the encounter.
The result ensures that Nadal reaches the semi-finals of the competition, which he has never won, as Group A winner, while Berdych is knocked out following Stanislas Wawrinka's win over David Ferrer earlier today.