Tiger Woods and his lookalike son, Charlie, enjoyed some quality father-son bonding time while watching tennis powerhouse Serena Williams at the U.S. Open.

Tiger Woods, 44, may be one of the most famous golfers in the world, but that doesnt mean he doesnt take the time to cheer on his fellow athletes from the sidelines! While recovering from his most recent knee surgery, the championship golfer attended the U.S. Open at Arthur Ashe Stadium with his son, Charlie, 10, in Queens, New York to watch legendary tennis pro Serena Williams, 37, take on Chinas Wang Qiang, 27, in the quarter-finals. This is the second time this week Tiger has stepped out with his son for some quality time together; they watched Rafael Nadal, 33, make it to the quarter-finals on Monday, and Tiger sang his praises for the pro tennis phenom on Twitter after the match, writing, “What a great night watching @RafaelNadal. Just an incredible performance and awesome way to close out the match. Thanks to @Rolex for hosting us.”

Tiger, who was dressed casually in a light blue Nike shirt and a pair of dark jeans, looked like he was having the time of his life with his son as they watched Serena cruise into a spot in the semi-finals after defeating her opponent in just 44 minutes. Tiger and Charlie were twinning in backwards hats, and just like his famous father, Tigers 10-year-old mini-me was also sporting a Nike top. Charlie also mirrored his dads movements and stances while cheering Serena on, triumphantly pumping his fist in unison with Tiger on at least one occasion during the match.

Erica Herman, 35, Tigers girlfriend of about two years, made a rare appearance with the duo as they watched Serena dominate the match. Erika looked cute and casual in a white silk camisole and ripped denim while taking in some family time with Tiger and Charlie.