Nick Kyrgios
Aug 2, 2017; Washington, DC, USA; Nick Kyrgios of Australia receives treatment from an ATP trainer during an injury timeout against Tennys Sandgren of the United States (not pictured) on day three of the Citi Open at Fitzgerald Tennis Center. Sandgren won 6-3, 3-0 (Ret'd). USA TODAY Sports / Geoff Burke

Australian star Nick Kyrgios can't catch a break. In his first match since retiring hurt in the first round at Wimbledon, the World No. 20 endured another injury-ridden defeat to World No. 106 Tennys Sandgren in the opening round of the Citi Open Wednesday in Washington D.C.

After going down 3-0 in the first set, Kyrgios chucked up a bagel, 6-0, within 20 minutes of play. The defeat marked the third consecutive tournament in which the 220-year-old Aussie has retired during a match. For most of 2017, Kyrgios has been dealing with persistent injuries to his left hip and shoulder. After pushing Federer to a classic five-setter at Key Bisycayne in April, and helping his country secure a Davis Cup victory over the Americans a month later, Kyrgios has fallen off the radar due to recurring injuries.

According to The New York Post, Kyrgios was met with boos at the William H.G. FitzGerald Tennis Center after informing his trainer that he was retiring. "When he told his trainer he no longer could play, he congratulated Sandgren and slowly exited the court to a crescendo of boos. Kyrios explained after the match that his physical struggles affected his preparation for the tournament, before the ATP cut him off in fewer than two minutes," read a report published Thursday.

Washington Open: Nick Kyrgios met with boos upon exit

“Just struggling, mentally, physically. This was a tough one. My shoulder kind of just came on today, I hadn’t been feeling it. And my hip has been fine. I’ve been very cautious with it, I haven’t been training enough, at all, to play a tournament like this so. I just wanted to see how it goes, but obviously I’m far from ready. … I just hadn’t hit enough balls.

"I don’t know, obviously the match intensity is different in practice but my shoulder’s a little bit sore. Obviously with the U.S. swing coming up I don’t think it’s really worth playing through here and jeopardizing my (chances to play) at the 2017 US Open," Kyrgios told reporters after the match, via The Washington Post.

Nick Kyrgios reportedly aggravated the hip injury in a fall at the Queen's Club back in June. After rating himself only "60 percent healthy" for The Championships, Kyrgios said he would contemplate hip surgery in the future. The Australian would likely have to take an extended break from the sport to undergo surgery.