CARLSBAD, Calif. -- U.S. Olympian Christina McHale held off Misaki Doi of Japan 4-6, 6-4, 6-4 to advance to the quarterfinals against No. 1 seed Marion Bartoli of France in the second round of the Mercury Insurance Open on Thursday night.
McHale, the No. 5 seed, needed three match points in the last game before she closed out the second-round match when Doi hit a backhand into the net.
McHale faced 19 break points, but Doi only converted three.
"I have to give credit to Misaki because she played really, really well. She made it hard for me," McHale said. "For my next match, I'm going to have to serve a lot better. I'm just happy that I found a way to pull it out."
Jankovic had a first-round bye and struggled throughout the match with her serve before closing out the match in the third set.
After the players traded service breaks, Jankovic broke the Hungarian's serve right back for a 4-3 lead and stayed ahead for good.
The former top-ranked player reached the quarterfinals for the first time in six appearances here. The Serbian will play qualifier Yung-Jan Chan of Taiwan in the quarterfinals
In other second-round matches, Urszula Radwanska of Poland cruised to a 6-2, 6-1 win over lucky loser Melanie Oudin, and No. 2 seed Dominika Cibulkova of Slovakia was a 6-2, 6-4 winner against New Zealand's Marina Erakovic.
Radwanska, the younger sister of world No. 2 ranked Agnieszka Radwanska, served well and took advantage of the American's subpar serve to control the match.
"Yeah, I was playing very good, and especially I was serving good," said Radwanska, who will represent Poland in the Olympics. "Probably that was the key because I was holding my serve."
Radwanska, who won 88 percent (23 of 26) of her first serves, reached the quarterfinals for the second straight week. She lost last week at Stanford to eventual runner-up Coco Vandeweghe.
Information from The Associated Press was used in this report.