American Coco Vandeweghe turned a second chance into a second-round match at the Bank of the West Classic on Monday.

Vandeweghe failed to make it out of the qualifying tournament but gained the main draw when Bojana Jovanovski was injured. She then took advantage of the opportunity by beating Melinda Czink of Hungary 6-4, 6-1.

"I was playing real solid off the ground and staying within myself," Vandeweghe said. "I started off serving well and hitting my spots, making a lot of good returns. Against a lefty, you have to do that, and get into a rhythm and get acclimated to their spin. I'm glad I got the experience, and I know was a little lucky to get into the main draw."

Seeded players Yanina Wickmayer and Chanelle Scheepers also advanced.

The fifth-seeded Wickmayer beat Chang Kai-Chen 7-5, 2-6, 7-5, while the sixth-seeded Scheepers downed qualifier Grace Min 6-4, 6-4.

Wickmayer, a Belgian who is ranked 37th in the world and reached the third round at Wimbledon, is looking for her first WTA title this year and the fourth of her career. She reached the quarterfinals at Stanford two years ago.

"The first match is always tough, especially coming from Wimbledon where you have to adapt to the hard surface," Wickmayer said. "I thought I stayed positive and played well in the good moments."

Chang, from Chinese Taipei, was playing her first main-draw match in a month.

In other matches, Michelle Larcher De Brito defeated Jarmila Gajdosova 5-7, 6-2, 6-3 and Great Britain's Heather Watson stopped American Sloane Stephens, 7-6(5), 4-6, 6-1.

The 19-year-old Stephens was the youngest player in the field. Serena Williams, who plays her first match on Wednesday, is the oldest at 30.

Canadian Stephanie Dubois was forced out of the tournament with a foot injury and seventh-seeded Petra Martic withdrew with an injury.

Vandeweghe did work through qualifying at Wimbledon before losing in the first round of the main draw, but on Sunday she dropped a 2-6, 6-2, 7-5 decision to Noppawan Lertcheewakarn.

Both Watson and Stephens celebrated their career high in singles ranking Monday. Watson entered play ranked No. 79 after reaching the third round at Wimbledon.

"It's tough playing someone who is your friend," Watson said. "I still think we gave it our all. I've played Sloane three times and all three times it has gone three sets."

Stephens was ranked No. 49 after also reaching the third round in England. She reached the round of 16 at the French Open.