New York, Aug 29 (IANS): Five-time champion Serena Williams was made to toil hard as she survived a scare against teenager American Catherine McNally in the second round of the US Open.

Pushed to the limit for the first set and a half, Serena withstood a brilliant effort from Catherine as she defeated the 17-year-old 5-7, 6-3, 6-1 in a contest that lasted one-hour and 54 minutes at the Arthur Ashe Stadium on Wednesday night.

"I think it's great because I want to be able to win matches where I'm not playing my best, play players who are playing great..be able to come through," Serena was quoted as saying in her post-match press conference by the WTA website. "I need to be tested, I guess."

With the victory, the No.8 seed kept her perfect record in second-round matches at the US Open intact -- improving to 19-0 in this round at this event -- two nights after reaching 19-0 in US Open first-round matches with her opening-night win over Russia's Maria Sharapova.

"You don't play players like her that have such full games," Serena said of Catherine. "I think she just overall played really well."

Serena will next face the winner of the other women's singles match between Dayana Yastremska and Karolina Muchova.