Serena Williams produced a remarkable first-set comeback against Silvia Soler-Espinosa to move into the second round of the China Open.
The world number one, who had been forced to retire in her last appearance on Tour at the Wuhan Open due to illness, emerged victorious 7-5 6-2 after a superb showing of resiliency.
Qualifier Soler-Espinosa capitalised on a dreadful start from the American to race into a 5-0 lead and looked set to condemn the US Open champion to a rare bagel, only for Williams to fight back and save three set points to finally get on the board.
Williams then denied her opponent on a further set point in the next game and proved unstoppable from there as she won seven straight games to take the set.
By that point Soler-Espinosa's fight had all but disappeared, allowing Williams to wrap up the victory in comfortable fashion and set up a second-round meeting with Tsvetana Pironkova after the Bulgarian beat Maria Kirilenko 6-4 6-1.
There was to be a slight first-round surprise on Monday, however, as France's Alize Cornet " the beneficiary of Williams' retirement in Wuhan " knocked out 10th seed Jelena Jankovic in three sets.
Just nine places separate Serbian Jankovic and Cornet in the rankings, and that fact was well demonstrated in a gruelling contest that saw the Frenchwoman prevail 7-5 3-6 6-4 in two hours and 39 minutes after turning around a 2-0 third-set deficit.
However, there were no difficulties for Jankovic"s compatriot Ana Ivanovic, the ninth seed hammering Belinda Bencic of Switzerland 6-2 6-1, while Flavia Pennetta and Lucie Safarova also progressed.
Pennetta overcame Christina McHale 7-6 (7-3) 6-4 but her Italian compatriot Camila Giorgi was beaten by Czech Safarova by an identical scoreline.
The all-Chinese clash at the WTA Premier hard-court event ended in victory for Peng Shuai as she went through in straight sets versus Zhang Kai-lin, although fellow home hope Zhang Shuai saw her challenge ended by Caroline Garcia of France.
Elsewhere in the draw there were wins for Mona Barthel and Lauren Davis.