pic Credit © John Minchillo/AP

At the U.S. Open, Serena Williams' advisor Tiger Woods becomes a fan.

On Wednesday, as Serena Williams prepared to play with the No. 2 player in the world in the U.S. Open, Tiger Woods sat down and joined her family in the Arthur Ashe Stadium stands.

After defeating Anett Kontaveit in three sets, Williams told reporters that he was "one of the main reasons I'm here" and "one of the reasons I'm still playing."

Williams, 40, and Woods, 46, who were both renowned athletes whose careers were coming to a close, developed a bond in which she looked to him for guidance.

Williams has only participated in four games over the previous 14 months, with just one victory.

"I was speaking with my friend Tiger Woods when I told him I needed his opinion on my tennis career. I said, "I don't know what to do; I think I'm over it [tennis], but maybe I'm not,"

"What if you just gave it two weeks, he asked Serena? You are not required to make any commitments. 

Simply give it your all on the court every day for two weeks and watch what happens.

Williams said she waited a month and then returned to the court, where it “felt magical to pick up a racket again.”