Cori Gauff came back from almost certain defeat at 6-4, 4-2 to beat Ons Jabeur in Lexington overnight, to reach the event semi-finals.
Gauff struggled early against the Tunisian, who broke her serve and powered home 6-4 before Jabeur looked to be safe, leading 4-2 in the second.
Jabeur led 2-0 before Gauff pulled it back to 2-2. The Tunisian led forced another error from the youngster and led 4-2 before the fightback began.
The American broke back in game eight with a deep return to level the score, holding at 15 and rattling off the fourth straight one following a drop shot error from Ons to steal the set 6-4.
Both players wasted break opportunities at the beginning of the final set, with Gauff having the upper hand from 1-1, taking all games to finally see off her gallant opponent.
World no. 49 Jennifer Brady is also through to the semi-finals after beating Marie Bouzkova 6-1, 6-2 in just over an hour.
Brady has been the in-form player of the week thus far, dropping just 11 games across her three encounters.
Semi-finals:
WTA Lexington Order of Play – Saturday, 15 August
CENTRE COURT Starting at: 11:00 am
[WC] Shelby ROGERS (USA) vs Jil TEICHMANN (SUI)
followed by
Jennifer BRADY (USA) vs Cori GAUFF (USA)
followed by, after suitable rest
Alexa GUARACHI (CHI)/Desirae KRAWCZYK (USA) [1] vs Marie BOUZKOVA (CZE)/Jil TEICHMANN (SUI)
WTA Prague Order of Play – Saturday, 15
CENTRE COURT Starting at: 11:00 am
TBF 6/2 0/1
Irina-Camelia BEGU (ROU) vs Sara SORRIBES TORMO (ESP)
followed by
Elise MERTENS (BEL) [3] vs Kristyna PLISKOVA (CZE)
followed by
Simona HALEP (ROU) [1] vs Irina-Camelia BEGU (ROU) or Sara SORRIBES TORMO (ESP)
followed by
Barbora KREJCIKOVA (CZE)/Katerina SINIAKOVA (CZE) [1] vs Monica NICULESCU (ROU)/Raluca OLARU (ROU) [4]