British number one Johanna Konta advanced to the Kremlin Cup quarter-finals with a 6-4 3-6 6-3 win over Australian Daria Gavrilova in Moscow.
Konta was a set and 2-0 up before her Moscow-born opponent, ranked 38, won six of the next seven games to level.
But Konta, ranked 44, went 3-0 up and won in two hours, nine minutes.
Meanwhile, at the European Open in Antwerp, Britain's Cameron Norrie needed only 63 minutes to beat Spain's Marcel Granollers 6-3 6-2.
He will play Argentina's world number 17 Diego Schwartzman in the round of 16.