What we learned on the Asian swing

SHANGHAI -- When it comes down to assessing the past couple of weeks in the men's game, three players had the most impact on the Asian swing: Novak Djokovic, Juan Martin del Potro and Rafael Nadal. Here's a look at the three, who have all already earned their spots in the coveted year-end ATP World Tour Finals.

China Is Novak Djokovic's Country: Anyone can tell you that it's not easy to come back to a tournament and defend your title. It becomes even harder to do when it's one of the prestigious Masters 1000 events billowing with the best players in the game.

But don't tell that to Djokovic.

Let's just say there's obviously something about China that makes Djokovic tick. Last week, he successfully defended his China Open title in Beijing, beating Nadal for the trophy. On Sunday, he also repeated at the Shanghai Rolex Masters, outlasting del Potro 6-1, 3-6, 7-6 (3). The victory was Djokovic's 20th consecutive match win in China, and with seven career titles in the country, it's the most trophies he's ever won in one nation.

Nevertheless, not everything that happened during this year's Asian swing left Djokovic smiling. Although it was inevitable, he found out last week in Beijing that he'd be relinquishing the No. 1 ranking to Nadal, who captured 10 titles, including two Grand Slam trophies in 2013. Asked about returning to the role of hunter after being the hunted since May 11, 2012, Djokovic was philosophical: "I knew that the rankings are going to change, considering the fact what Nadal has achieved this year. It was a matter of a moment or a week or whatever when he's going to take No. 1, because he's had by far best results this year. I knew that, but I still keep on believing in myself and keep on working hard, being very motivated to win every tournament that I play in. … I'm still inspired to play my best tennis."

The casualness in which he discusses losing the No. 1 ranking presents a picture that it really didn't bother him. But his attitude -- frequently cranky on court -- suggests otherwise. In Shanghai, he was clearly frustrated and spent time arguing with umpires and doing things like swiping at the Rolex time clock.

Successfully defending his two China titles decreased the point margin between Nadal and Djokovic, and there is a small possibility the Serb could end the season as No.1. But for now, that honor belongs to his chief rival, Nadal.

Don't Underestimate DelPo: Del Potro is playing some of the best tennis of his life. According to the Argentine, he's surpassed his level that carried him to his lone Grand Slam victory at the 2009 US Open. Most wouldn't argue with him on that assessment, particularly if they saw his near flawless 6-2, 6-4 undoing of Nadal in the Shanghai semifinals. Playing on a very speedy court, del Potro continually inched closer into the court as the match wore on, and his flat, powerful groundstrokes prevented Nadal from having enough time to set up his shots. It's not often that fans find Nadal rushed in playing a point.

Although del Potro lost the Shanghai final to Djokovic, be assured he didn't play poorly. Del Potro might not have matched his in-the-zone performance over Nadal, but he was definitely in good form. To add to his recent success, del Potro won his third title of the year at Tokyo last weekend.

Del Potro is definitely back in the conversation, a potential champion at every tournament he enters. Yet when asked about being a major factor in the same vein as Djokovic, Nadal and Andy Murray, he still seems programmed to demur.

"I think they are still the favorites for each tournament," del Potro said. "But I believe in myself. I'm very confident. I'm very pleased with my level. I'm very honest with me. I think if I'm healthy and I play like today or yesterday, I will have a chance to play good battle like we did today. I love this sport. I love playing these kind of matches even if I lose."

Rafa Rules Rankings Again: Is Nadal experiencing a post-return-to-No. 1 letdown? He's traveling home to Spain after his two-week China trip without a winner's trophy in hand. Last week, Nadal fell to Novak Djokovic 6-3, 6-4 in the Beijing final before losing to del Potro in the Shanghai Rolex Masters semifinal.

Nadal fans, however, should not despair. Although he didn't pick up his 11th title of the season -- he has a 68-5 record overall and is 29-2 on hardcourts this year -- it was not a case of his playing badly. In fact, Nadal actually played high-quality tennis in the Shanghai semifinals, although his serve at times was a bit streaky. Del Potro, as it turned out, was in an impenetrable zone that no player was likely to invade.

So when Nadal said he's leaving Shanghai in good spirits, it was obvious he was telling the truth.

"He played amazing," Nadal said of del Potro on Saturday. "Very few times I played against a player with a level like today I played against. Nothing to say on me. … So I go home with the calm that I did all what I had to do and I played today against a player that was better than me tonight."

No matter how Nadal fares in the last few weeks left of 2013, his return to the tour in February after seven months couldn't have been choreographed any better. With his rehabilitated knees in fine-tuned working shape, Nadal came back stronger than before, winning 10 titles in 13 finals played this year. Nadal is currently in position to end the year as the world No. 1 for the third time in his career. To say all his accolades are well-deserved is an understatement.