Rafael Nadal's first-round loss at this year's Wimbledon was an example of what will become a permanent problem on grass courts.
Despite missing about half a year due to a knee injury, the Spanish player came into the third Grand Slam of the season playing as well as he had in his entire career. He won 43 of his 45 matches with an incredible seven titles in nine tournaments.
In the two events Nadal failed to win, he reached the finals before losing.
The King of Clay was completely dominant, leading many to believe he was ready to contend for his third title at the All England Club. Unfortunately, that was not meant to be as he was dropped in the first round by Steve Darcis.
While the early loss was clearly a disappointment, the grass court would have prevented him from making a deep run regardless.
Nadal has been successful throughout his career due to his defensive ability. He covers an amazing amount of ground in rallies and prevents his opponent from getting virtually any winners during the match.
He returns serves with amazing consistency throughout his career, winning an impressive 33 percent of return games. His marks of 34 percent of points won against the first serve and 55 percent against the second serve are among the best of all time.
On clay, he is able to sit back and wait for opponents to make a mistake while he simply paces back and forth across the court. With his fitness, there are few players able to challenge him in long rallies, and he outlasts players.
However, the grass court is more slippery, which makes it tougher to change directions and make cuts on the court. This takes away Nadal's biggest advantage.
In the past, the lefty was quick enough to overcome this issue. He could make slower cuts before chasing down balls on the other side of the court. After lots of mileage on his legs and the recent knee issue, he is no longer able to do this.
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The other problem is his serve, which has never been as strong as some of the other competitors on tour.
Those that do well at Wimbledon and other grass tournaments are those who can get fast serves and put them in perfect locations. Roger Federer has done this throughout his career, and as a result has seven career titles at the English event.
Nadal hardly has the biggest serve in the world, and it has become easier for opponents to put it in play recently.
While he and Darcis had similar serving speeds in their match, the underdog had 13 aces compared to only six by Nadal. Although this seems insignificant, the three-set contest went to two tiebreaks and was truly decided by just a few points.
Nadal's lack of aces has been a problem all season long despite his overall success. He has fewer aces per service game in 2013 than he has had in a long time.
As you can see, his best performance with the serve came in 2010, which is also when he last won at Wimbledon.
Unfortunately, Nadal is no longer able to blow his serve past opponents. This will continue to hurt him on grass against opponents who have stronger return games.
By winning the career Grand Slam, the superstar has shown that he can get it done on any surface. However, his success on grass is likely coming to an end.
Note: All statistics courtesy of ATPWorldTour.com.
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