Serena Williams has insisted that it is not a "worry" that she was not given much of a test in the first round of the US Open.
The match lasted just 30 minutes as Williams's opponent Vitalia Diatchenko was forced to retire in the second set at Flushing Meadows.
The 33-year-old American, who is on course to grab a calendar Grand Slam, managed to seal a spot in the second round with a 6-0 2-0 triumph.
"I don't think that's a worry because my practices are really intense and I really fight really hard in my practices," ESPN quotes Williams as saying. "I know that every match is a challenge. I have to be ready for everything.
"It was a really good feeling going out there. You know, just taking it all in, having those nerves, but at the same time just being ready for whatever happens."
Williams has played 17 three-set matches in a year, losing two.
