Updated

U.S. Olympian Christina McHale saved a set point, then used a late service break to pull out a 7-6 (5), 7-5 win over Jarmila Gajdosova in the first-round of the Mercury Insurance Open on Tuesday.

McHale, the No. 5 seed, struggled against the Australian, and both players held serve late into each set. But McHale took advantage of Gajdosova's mistakes to claim the tiebreak and hit some late winners to claim the victory.

"It wasn't easy out there," said McHale, who pulled out of Stanford last week with a sinus infection. "Jarmila played really well, especially served really well. I was just happy to be able to pull that one out."

American CoCo Vandeweghe, fresh off losing to Serena Williams last week in her first WTA final, will play No. 8 seed Chanelle Scheepers of South Africa in the night match.

No. 7 seed Yanina Wickmayer of Belgium dropped the first set 7-6 (6) to qualifier Yung-Jan Chan of Taiwan before retiring with a lower back injury.

The 20-year-old McHale was trailing 5-4 in the second set when she saved a set point with an ace. McHale then used the first service break to take a 6-5 lead.

McHale, playing in her first tournament since losing in the third round at Wimbledon, advanced on her first match point when Gajdosova hit a backhand into the net.

The players were on serve in the first set before Gajdosova broke through in the 11th game with two great service returns for winners. But McHale broke right back to force the tiebreak.

Trailing 5-4 in the tiebreak, Gajdosova dumped an easy approach shot into the net, and McHale finished off the set two points later when Gajdosova hit a forehand into the net.

"I just kept fighting," McHale said. "All of the games were close and she was playing really well, so it was tough."

In other first-round matches, American Vania King defeated Kai-Chen Chang of Taiwan 6-1, 6-4; Marina Erakovic of New Zealand beat Anne Keothavong of Great Britain 6-4, 6-0; Heather Watson of Great Britain ousted Eleni Daniilidou of Greece 6-3, 6-3; and Melinda Czink of Hungary beat qualifier Sesil Karatantcheva of Kazakhstan 6-2, 4-6, 7-5.