Novak Djokovic in seventh heaven after clinching year-end No. 1 spot

Willie Grace | 11/14/2014, 6:06 p.m. | Updated on 11/14/2014, 6:06 p.m.
"It's a great deal of happiness knowing what I've been through the entire season in order to get to where ...

(CNN) -- A mixed season for Novak Djokovic is at least ending on a high.

Djokovic, the world No. 1, clinched that position in the year-end rankings for the third time when he crushed Tomas Berdych 6-2 6-2 in yet another lopsided encounter at the World Tour Finals in London.

In doing so Friday, the Serb became the seventh men's player to achieve at least a treble, joining Pete Sampras, Roger Federer, Jimmy Connors, Ivan Lendl, John McEnroe and Rafael Nadal.

"It's a great deal of happiness knowing what I've been through the entire season in order to get to where I am and finish the year as No. 1," said Djokovic, who became a dad and got married in 2014 but also lost his first coach, Jelena Gencic, and suffered a wrist injury.

"It's one of the ultimate challenges in this sport."

Sampras leads the way with six year-end No. 1 men's finishes and with Djokovic going a perfect 3-0 in the round-robin stage this year, he ended Federer's slim hopes of tying the American.

Djokovic celebrated by taking part in a group hug with his entourage -- which included coaches Marian Vajda and Boris Becker -- at the side of the court.

"Because Nadal and Federer are so good for so many years, they always make you win at least one or two grand slams if you eventually want to be No. 1, and of course with consistency, because they've been so consistent with their results.

"I know how difficult it is. It's why I'm proud of this achievement."

Djokovic, the two-time defending champion at the year-end championships, was almost assured a spot in the semifinals even before he faced the 2010 Wimbledon runner-up -- but he made sure of progressing with an emphatic display.

It's almost as if Djokovic was trying to better the second-ranked Federer, who on Thursday evening thumped Andy Murray 6-0 6-1 in a score no one could have anticipated.

Friday's drubbing in Group A was a little more predictable, given that Djokovic owned a 16-2 record against Berdych and pummeled his opponent 6-0 6-2 in the final of the China Open in Beijing in October.

His best shot could have been a piercing backhand down the line at 5-1 in the second set that brought a smile to the face of Vajda, his lone coach prior to the arrival of Becker.

In three matches this week, Djokovic has dropped a paltry nine games. And when he forced a forehand error from Berdych on match point, Djokovic saw his winning streak indoors rise to 30 matches.

"He just secured his spot for the No. 1 player in the world -- I think it shows how great he is," said Berdych.

Djokovic will face Japan's Kei Nishikori on Saturday in a rematch of their U.S. Open semifinal. That day marked one of Djokovic's low points in 2014, as the 27-year-old fell in four sets to Nishikori when he was the substantial favorite at Flushing Meadows.

But playing in London might help Djokovic. It was in London in July that Djokovic earned his lone Grand Slam title of 2014 on the grass at Wimbledon.

Federer, who finished at 3-0 in Group B, will meet his fellow Swiss and Davis Cup teammate Stan Wawrinka in the last four.

Wawrinka simply needed to win just three games against the player who beat Nishikori in the U.S. Open final, Marin Cilic, on Friday evening to book his place in the semifinals for the second straight year.

Cilic missed the last regular season event, the Paris Masters, with an arm injury and says he's fatigued. His results in London would back up that claim, but he did salvage pride in the final group match.

Wawrinka eventually prevailed 6-3 4-6 6-3 over Cilic, only the second match in 12 group games to go the distance.

It was the Australian Open champion's second victory in Group A, but he was soundly beaten in straight sets by Djokovic in his other encounter.

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