Venus Williams’ return to form ahead of the US Open was thwarted on Tuesday as Lucie Safarova sent the American crashing out in the first round of the Cincinnati Masters.
A week after beating Angelique Kerber, Carla Suarez Navarro and sister Serena Williams – her first win over the world No 1 in five years – en route to the Montreal final, Venus made a premature exit at the precursor to the US Open.
Williams, twice winner of the final Grand Slam of the year, returned to the world top 20 for the first time since March 2013 on Sunday before losing 6-7 (2/7) 6-3 6-4 to Czech ace Safarova.
After trading holds through 10 games Williams and Safarova then exchanged breaks of serve to force a tie-break, which the American made light work of.
However Safarova's riposte, claiming the lone break of the second set at 3-2, took the match into a deciding set and after three, three-setters in Montreal Williams displayed signs of fatigue.
Safarova raced to a 5-1 lead in the final set but the 27-year-old had to weather a Williams fightback before she could close out the match and book her place in the second round.
"It was definitely a quick turnaround," Williams told the WTA website after returning to court just 48 hours after her Montreal final defeat.
"But she just played so well. No matter what shot I hit, she hit a winner, or if I hit it really deep, she somehow managed to control it down the line.
"I think she got a little tight at 5-1, so I had some chances to come back, but that's a deep hole. Sometimes it's just tough to play opponents who are hitting everything off every shot."
Safarova will now face Kazakhstan's Zarina Diyas, who beat fellow qualifier Irina-Camelia Begu in two tie-breaks.
Carla Suarez Navarro advanced as the 15th seed beat Tsvetana Pironkova 6-3 1-6 6-2 while Christina McHale beat Nicole Gibbs 4-6 6-3 6-1 in their all-American clash and Kurumi Nara beat Romina Oprandi 6-0 6-2.
Ekaterina Makarova was a comfortable winner over Daniela Hantuchova as she progressed 6-2 6-2 but 14th seed Sara Errani was made to work hard to beat Yanina Wickmayer 7-5 3-6 7-6 (7/2).
Svetlana Kuznetsova needed three sets to overcome Camila Giorgi 6-4 6-7 (7/9) 6-3 while Annika Beck beat Garbine Muguruza 6-3 2-6 6-3 and Sabine Lisicki was a 6-3 2-6 6-2 winner over Roberta Vinci.
Home favourite Sloan Stephens was also a winner as she beat Andrea Petkovic 6-3 6-3.
The three seeds in second-round action all progressed although Maria Sharapova had to recover to beat Madison Keys in three seets.
The fifth seed dominated the first set but although Keys hit back to level the match, Sharapova regrouped to win 6-1 3-6 6-3.
Second seed Simona Halep and 12th-ranked Caroline Wozniacki recorded straight-set wins. Halep defeated Kirsten Flipkens 6-4 6-2 while Wozniacki brushed aside Shuai Zhang 6-2 6-3.