Spain's Rafael Nadal is heading into the U.S. Open, which begins on Monday, with an opportunity to grab the top spot in the ATP rankings from Serbia's Novak Dkojovic.

Nadal will have to win the year's last Grand Slam event and hope Djokovic does not make the final to get back to No. 1, a ranking the Spaniard last held on June 4, 2011, and lost to the Serbian.

The top of the ATP rankings were unchanged this week, with Djokovic at No. 1, Nadal at No. 2 and Britain's Andy Murray, the defending champion in New York, at No. 3.

"Last year, I watched this event on television, this year I have the opportunity to play and that is unbelievable," Nadal said during a press conference over the weekend marking Arthur Ashe Kids Day, the kickoff event for the U.S. Open.

The 27-year-old Nadal, who won his 8th French Open title on June 9, was off the ATP Tour for seven months due to a knee injury that plagued him after his loss at the 2012 Wimbledon tournament.

Nadal's first opponent at the U.S. Open will be American Ryan Harrison on Monday and he could meet longtime rival Roger Federer of Switzerland in the quarterfinals.

The Spaniard has been on a tear since returning to action in February, playing in 11 finals and winning nine titles.

His only setback came at Wimbledon, where Belgium's Steve Darcis knocked him off 7-6 (7-4), 7-6 (8-6), 6-4, marking the first time Nadal lost in the first round of a Grand Slam event.

A win in New York will bring Nadal a total of $3.6 million, with $2.6 million coming from prize money and $1 million from the US Open Series bonus. EFE