Jelena Jankovic came through a tough battle against Zheng Jie to reach the US Open fourth round.
Second seed grinds down Wimbledon semi-finalist
Jelena Jankovic came through a tough battle against Zheng Jie to reach the US Open fourth round.
Jankovic, the number two seed, was forced to work hard for her 7-5 7-5 victory by the Wimbledon semi-finalist, who was always likely to be a dangerous opponent.
Both players struggled on serve through a match which lasted two hours and nine minutes and which produced 14 breaks of serve.
Jankovic claimed the lion's share in either set to progress, but it could have been different had Zheng taken her chances.
The first three games went against the serve, before Jankovic finally held to establish a 3-1 lead.
However, Zheng levelled with a break in the eighth game, triggering a run of four successive games against the serve before Jankovic held again to take the set.
Zheng moved 2-0 ahead at the start of the second set, but the Serb won the next three games to move ahead at 3-2.
She stayed out in front and served for the match at 5-4, but Zheng recovered well to level the set at 5-5 with her sixth service break of the match.
Once again the Chinese player followed a break by dropping her serve and she then missed eight break points as the tension mounted in the 12th game.
Jankovic squandered four opportunities to settle the match, but eventually she prevailed with a rare service hold.
