Azarenka preaches patience after battling through in Silicon Valley

Victoria Azarenka is determined to remain patient in her search for improved form after battling into round two of the WTA Silicon Valley Classic.

A two-time Australian Open champion and former world number one, Azarenka has endured a prolonged spell away from the court due to a protracted custody battle.

On Monday, in her first outing since Wimbledon, she overcame fellow mother Kateryna Bondarenko in a gruelling three-setter, eventually prevailing 6-3 6-7 (7-9) 7-5 in two hours and 40 minutes.

In an on-court interview following her win, the 29-year-old said: "It's a really challenging time for me and my game right now. You can see with my game, there's a lot of ups and downs. The important thing is that I'm here, I'm fighting hard, and I try to do my best. That's all I can ask of myself, but it's not easy.

"Everyone expects to have results right away - I do too - but I need to be patient, and keep working hard."

Azarenka will be an underdog in her second-round tie against top seed Garbine Muguruza.

Monday's final match saw American teenager Ashley Kratzer survive a late wobble to overcome Alison Riske. Kratzer triumphed 7-5 in the third having led 5-1 only to be pegged back to 5-5.

There were wins in straight sets for Maria Sakkari, Sofia Kenin, Ajla Tomljanovic and Danielle Collins, while Serena Williams is among those in action on Tuesday.