China’s Li Na returns the ball to France’s Kristina Mladenovic during their French tennis Open first round match at the Roland Garros stadium in Paris today. (Miguel Medina/AFP/Getty Images)

Much like age, perhaps, rank ain’t nothing but a number — at least in today’s French Open faceoff between reigning Australian Open champion Li Na, who ranks second in the world, and Kristina Mladenovic, who ranks just 103rd.

Mladenovic handily beat Na, 7-5, 3-6, 6-1, at Roland Garros stadium, but not by playing like a champion. The French contender made 25 unforced errors. But luckily for her, her Chinese opponent played worse. Na made 37 unforced errors including one during the last shot of the match:

Preceding Na’s upset was the Australian Open men’s champion Stan Wawrinka’s. The Swiss player was eliminated in four sets by 41st-ranked Guillermo Garcia-Lopez during Monday’s first-round action. The Spaniard beat the third-ranked Wawrinka, 6-4, 5-7, 6-2, 6-0. Much like Na, Wawrinka also played terribly. He made 62 unforced errors compared with Garcia-Lopez’s 28.

After the match, Wawrinka said via Sports Illustrated:

“The match wasn’t good at all. I was trying to find my game, trying to find to be aggressive, trying to find anything, and I didn’t… It’s a big disappointment for sure. I’m really sad with that loss, but cannot change. I have to accept. I have to see what was wrong, to see what I want to change, the way I want to do it, and now think about the future and not about that match anymore, because I can’t change the result.”

According to Fox Sports, this is the first time that both Australian Open champions have lost in the first round of the French Open. At least no reporters mistakenly congratulated him after the loss

Another upset came later Tuesday when No. 13 seed Caroline Wozniacki of Denmark lost in three sets to Belgian Yanina Wickmayer, 7-6, 6-4, 6-2. Wozniacki had a lot of attention on her going into the match, having just had her engagement end (messily) to golfer Rory McIlroy. Rubbing salt in the would, perhaps, McIlroy, who broke up with Wozniacki, went on to win the BMW PGA Championship this weekend after the breakup last week.