Kevin Anderson’s wife Kelsey O’Neal must have left the court in pure joy for more than one reason.

One, because her husband won his opening match at the ATP Finals, pulling off a 6-3 7-6 conquest of Austria’s Dominic Thiem on Sunday.

Second was because of what happened after the match (hint: it was her birthday).

Well, Anderson surprised her as he sang ‘happy birthday to you’ during the post-match interview. And fans were kind enough to join in in wishing Kelsey.

No wonder, she wore a bright smile on her face all through.

Meanwhile, Anderson, who reached the Wimbledon final earlier this year, will look to continue his giant-killing spree when he takes on Swiss ace Roger Federer on Wednesday.

Do you see him making two in two?

The @TheO2 is used to hosting music concerts, but none quite like this ????????

Happy birthday, @KelseyOAnderson! ????@KAndersonATP #NittoATPFinals pic.twitter.com/cGW8ZQe9Zg

— Tennis TV (@TennisTV) November 11, 2018