Top seed Ekaterina Makarova advanced to the semi-finals of the Citi Open in Washington after beating sixth seed Irina-Camelia Begu 6-4, 2-6, 6-1.
The first set was a fairly close affair, but Makarova came out on top 6-4 after claiming the lone break of the set. Begu came roaring back in the second set, capitalising on the two break points she engineered to take the set 6-2.
But, Makarova proved to be too much for Begu to handle in the third set. After the pair held serve to open the decider, Makarova the proceeded to win the next five games, breaking the Romanian twice in the process, to triumph in an hour and 40 minutes.
Makarova will face Anastasia Pavlyuchenkova in the semi-finals after she recorded a come-from-behind 2-6, 6-1, 7-6 (5) win over Christina McHale.
The other semi-final will see second seed Samantha Stosur taking on Sloane Stephens.
Stosur progressed to the final four after her quarter-final opponent, Monica Niculescu, pulled out midway through the first set with an abdominal strain.
Stephens meanwhile defeated wildcard Louisa Chirico 6-4, 6-4 in one hour and 28 minutes to book her spot in the semi-finals.