Philadelphia, PA (SportsNetwork.com) - Maybe Rafael Nadal won't capture a 10th French Open title in June?

The great star has been hampered by injuries as well as a bout of appendicitis over the last 10 months ... and it's starting to show.

Just this week, the former world No. 1 lost to scrappy Italian Fabio Fognini in the third round in Barcelona on Nadal's beloved red clay.

As a matter of fact, the under-performing Nadal has lost to Fognini in their last two matches, with the other setback occurring in a semifinal in Rio back in February.

The 14-time Grand Slam ace has currently lost two of his last three matches and failed to reach a final in his last four tournaments, this after winning a title in Buenos Aires on March 1. And two of the losses came prior to the quarterfinals (Barcelona and Miami).

Nadal headed to Barcelona not as a reigning champion, but as an eight-time winner at the event on his home soil, with his last title there coming two years ago. But in stunning fashion, he's now failed to capture the Barcelona crown in two of his last three trips.

Back to this 2015 campaign, Nadal is a mortal 19-7, and that includes a disappointing quarterfinal exit at the Australian Open in January. And he's appeared in only one final in seven tournaments.

Hmm.

As a matter of fact, a hobbled Rafa has failed to get past the quarterfinals at the last three majors, one of which was last year's U.S. Open that he missed altogether because of physical problems. In addition to the QF loss in Melbourne, the Spanish bull came up a fourth-round loser at Wimbledon last summer.

Nadal's last three trips to Wimbledon have resulted in second-round, first- round and fourth-round losses, respectively.

And he's missed two of the last three U.S. Opens because of injuries (although he did capture the title in New York as recently as 2013).

The soon-to-be-29-year-old Mallorcan has admitted to having confidence issues right now, and I think a loss, to Fognini, on clay, in Spain, would be a pretty good indicator of that.

Rafa's ranked fourth in the world and is in danger of falling behind current world No. 5 Kei Nishikori, the 2014 U.S. Open runner-up who just seems to keep gettin' better.

Nadal has vowed to keep no stone unturned in his bid to return to top form.

Plagued by a lack of consistency and a lackluster forehand in recent weeks, he said: "My challenge is to get back to my best level again and I will work until that happens. I have the conviction that it will happen.

"Until I sort out the ups and downs I'm suffering from this season, I will continue to be vulnerable," Nadal added.

The question is whether Rafa can pull himself out of this funk in time for another run at Roland Garros, which starts late next month. Because if he's not ready to go all the way there, I know who is.

Novak Djokovic.

A hungry Djokovic needs a French Open title to complete his career Grand Slam trophy case, having lost to his long-time rival Nadal in two of the last three finales in Paris.

Nadal has won five straight Coupes des Mousquetaires, and maybe he will make it six straight and 10 overall this spring. But right now, he's playing like a guy who would be an also-ran at the lone clay-court Slam. His clay-court Slam!