Novak Djokovic, Rafael Nadal Rivalry: Djoker Blames Rafa for His Career Grand Slam Failures [VIDEO]

He's been the No. 1 men's tennis player in the world three of the last four years, but Novak Djokovic knows he has a sizable hole in his career résumé and only one man to blame for it.

Rafael Nadal.

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Djokovic told IBNLive.com that a major goal for 2015 is completing his career grand slam by winning the one championship that so far has eluded him - the French Open.

"I have been pretty close to winning the French Open title and have played a few finals and semi-finals but I have a problem, his name is Nadal. He is not going away, that's for sure," he told reporters at the Indira Gandhi Indoor Stadium in New Delhi earlier this week, as IBNLive.com reported.

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"I'm going to push hard for it; I'm going to keep on trying each year. Hopefully I can keep on going, I have that self-belief, I know I can do it and hopefully by the end of my career I am going to get one trophy there."

Nadal has won the French Open in nine of the past 10 seasons (from 2005-08 and 2010-14), including wins over Djokovic in 2012 and 2014.

Djokovic has seven career grand-slam titles, including four Australian Opens, two Wimbledons and one U.S. Open.

Djokovic participated in the inaugural International Premier Tennis League in New Dehli, a team-format of tennis that he says will help him during the 2015 season.

"I can take so many new things from the IPTL. I have new friendships, new relationships and, most importantly, I can take a lot of good, positive energy from here," Djokovic said, according to gulfnews.com. The format is very special for tennis. Most of the guys have been travelling for three weeks and I can see that it's a lot of fun and excitement. I was in India for three days and the team spirit that we got to feel is amazing. This is something that we don't get to experience much on the Tour as we stick to ourselves and our teams. Here there is a full team supporting you and I love it."