Upsets in the US Open aren't uncommon, but they can still be shocking to hear. Take for example Monday's ground-shaking win by Daniel Galan over no. 4 seed Stefanos Tsitsipas. Galan went down to work early, winning the first set, 6-0, and then followed that up with a 6-1 win in the second set. Stefanos Tsitsipas found his groove with a 6-3 set 3 win and appeared to be on the verge of tying it all up in the fourth set but Galan simply wouldn't allow himself to collapse, finishing the match with a 7-5 third-set score in his favor.

Stefanos Tsitsipas was understandably disappointed over the outcome of this very first match in the 2022 US Open, but respected the way Galan played the match. “He dominated the match,” Tsitsipas said, via ATP Tour's website. “I just couldn't get into it.”

Galan's service game was on point against Stefanos Tsitsipas, as the Colombian put 63 percent of his first serves into play and won a point on 74 percent of them. Stefanos Tsitsipas was off this game, with 57 unforced errors to just 36 by Gala, who also converted 7 of 18 break-point opportunities.

It's also worth noting that this is the second time in his career that Stefanos Tsitsipas has exited the US Open in the first round, having dealt with that painful fate back in 2019. As for Galan, who had to go through the qualifying rounds to make it to the tournament pepper of the 2022 US Open, he will look to sustain his momentum as he is set to take on Australian Jordan Thompson in the second round.