In a Wimbledon doubles' match with her sister Venus on Tuesday, Serena Williams appeared to be disoriented and ill, losing three straight games in a painful-to-watch bit of tennis before the pair forfeited the match. Although the crowd cheered Williams on, double fault after double fault, it quickly became clear that she wasn't fit to play. 

Here's a clip of the match before the pair withdrew from the tournament (a longer video is available, via Wimbledon). But we warned: we mean it when we say that this is hard to watch. 

In another bizarre turn of events, Serena was eliminated from the women's singles tournament in the third round of play. Her recent record shocked USA Today's Chris Chase: 

Williams is now 6-3 at Grand Slams this year and has failed to make the quarterfinals in four of her last five majors. It’s a baffling and precipitous fall for the woman who entered 2014 having won four of her last six Slams and playing some of the best tennis of her life. Consistency was never a hallmark of Serena’s game, but neither was losing to opponents who aren’t on her level.

At this point, we don't know why Williams performed poorly today, or if it's connected to her shaky record as of late. Before the match, the Associated Press reported, Serena received medical attention.

Update:  Later on Tuesday, Serena Williams explained in a statement to the AP that her performance in the doubles' match was due to a "viral illness." Serena said: "I am heartbroken I'm not able to continue in the tournament," adding, "I thought I could rally this morning, because I really wanted to compete, but this bug just got the best of me."