Tiafoe and Sabalenka react to Federer's presence at Arthur Ashe night session

Although Frances Tiafoe and Aryna Sabalenka were focused on important business on court during Tuesday's night session, both players admitted to being aware of the star presence of Roger Federer, who watched from the stands of the Arthur Ashe Stadium.

Federer, who won five consecutive titles at Flushing Meadows from 2004 – 2008, was seen in one of the stadium boxes, speaking to former US Open semi-finalist Tim Henman, and Commissioner of the NFL, Roger Goodell.

The Swiss legend first saw Sabalenka overcome Zheng Qinwen 6-1, 6-2 in the women’s quarter-final. He then watched American hope Tiafoe defeat Grigor Dimitrov 6-3, 6-7(5), 6-3, 4-1 to advance to the men’s semi-final as the Bulgarian retired with injury.

Tiafoe spoke about the feeling of having the 20-time Grand Slam champion watching: “Yeah, I mean, that was pretty sick. Obviously, I wasn't thinking about it that much. The last couple years of Laver Cup you kind of get used to that, seeing him in the stands.”

The No. 16 in the PIF ATP Live Rankings also joked about Federer’s trademark sophistication: “The way he looked in the suites is the same way he looked when he was playing. No sweat. Tees ironed perfect. What's up with this dude, man? Hair perfect.

“What a guy. What a legend. So nice he's enjoying his life, doing his thing, just popping in wherever he kind of wants to, and everyone embraces him. Unbelievable wherever he goes. I mean, he's such an icon.”

Sabalenka spoke about the effect of Federer’s presence on her game: “I saw him there, saw him on the big screen. I mean, I'm pretty sure he came to watch Tiafoe and Dimitrov, but still, I was like, ‘Okay, I have to play my best tennis so he enjoys it’.

“I had to show my skills you know, slice skills, come to the net and all that stuff.”