The tennis season is over after Sunday's dramatic Davis Cup finale.
We present 10 burning questions heading into next year.
Which Roger Federer will we see in 2011?
Expect Federer to play the way he did at the year-end championships. He adopted a more aggressive approach during the U.S. Open Series and stepped it up further in London against the varied quintet of David Ferrer, Andy Murray, Robin Soderling, Novak Djokovic and Nadal. As Federer said himself, when things got a little tight in matches, he didn't turn passive -- unlike a few times in the past.
"I always believed in a plan from start to finish," Federer told reporters. "The first match against Ferrer, I always stayed true to how I wanted to play."
The years of Federer dominating -- think 2004 to 2007 -- are over. But he'll perform better at the Slams in 2011 compared with the previous six months. Bare minimum, he won't falter prior to the semis.
Can Federer regain the No. 1 ranking?
Prior to the year-end championships, you wouldn't have thought so. Now, you never know.
"There's a chance, based on the way he played and how motivated he is," ESPN analyst Patrick McEnroe said in an interview. "Overall, I think it's going to be tough because I still think week in, week out, he's going to lose a bit more. But it would be an unbelievable effort."
And an unprecedented one if Federer could finish 2011 at No. 1. No men's player has lost the year-end top ranking and regained it twice.
How much will his win over Nadal help him?
Federer, if he needed it, received confirmation that all the hard work he's putting in and changes to his game are paying off. His emotional celebration said it all.
Further, in beating Nadal, he got a jolt of confidence. Nadal had triumphed in six of their previous seven encounters, including a trio of Grand Slam finals.
"It was huge for him to get a win over Rafa in a big match," McEnroe said. "It's been a few years. I think that will help him considerably for next year if they meet in a Grand Slam final."
How much credit goes to Fed's new coach?
Paul Annacone should take his fair share of credit. Let's face it, if Annacone hadn't joined Team Federer, would the Swiss have tinkered with his style? Annacone had considerable experience working with attack-minded players in Pete Sampras and Tim Henman.
But as former top-10 pro Marc Rosset pointed out, Federer, nearing 30, deserves most of the plaudits.
"After winning 16 majors, you can just sit in your chair and say, 'OK, why should I change anything?'" Rosset, now an analyst for Swiss television, said in an interview. "When he didn't win majors this year as he did in the past, he said, 'I have to do something.'"
Can Nadal repeat his incredible 2010 season?
Given his mental toughness and the changes he has made to his own game, yes. More than a few maintain that Nadal is simply a grinder, which is so far from the truth.
Sure, he plays long points and matches. Yet what part of his game hasn't improved? The serve? Volley? Backhand slice? Standing closer to the baseline? He has become more aggressive himself, in his own fashion.
Nadal was cautious, and somewhat paradoxical, when assessing 2011.
"[I] can have a better season, yes," Nadal told reporters in London. "You can win in every place. But it's difficult. In my case, it's almost impossible."
Can Rafa stay healthy?
That's still the most important question as it pertains to Nadal, with his knees remaining the major concern.
Despite his gargantuan season, Nadal retired from his quarterfinal at the Australian Open, missed his beloved Barcelona Open and overcame some knee woes to prevail at Wimbledon in 2010. Last year, it was the knee and stomach (U.S. Open).
As in 2009, if Nadal is forced to the sideline for any extended length, Federer should breeze past the 24-year-old.
On the positive side for Nadal fans, he contested a mere 17 tournaments in 2010, matching his lowest total since becoming a regular on the tour. He also played in 17 in 2006, although only because he was injured the first 1½ months.
Barring something unforeseen, he'll be 100 percent as he tries to complete the "Rafa Slam" in Melbourne.
What can we expect from Andy Murray?
Murray possesses all the physical tools to win a major, and we all know he has beaten Roger and Rafa multiple times in the past. But he seemingly can't perform consistently when it really matters -- in Slams. Worryingly, Murray might be believing that himself.
With Federer's resurgence and Nadal's almost invincible form, the task won't get any easier for the Scot.
Murray hasn't even been able to routinely go deep at majors; in the past dozen, he has exceeded the quarterfinals four times.
Will Andy Roddick bounce back?
Yes. Rocket scientists don't need to be consulted to understand why Roddick's results dipped at Grand Slams. For most of the year, he wasn't healthy.
It began at the Australian Open, when shoulder and neck injuries did him no favors in a five-set loss to Marin Cilic. Then came mono, which not only hampered Roddick at Wimbledon but also affected his training routine heading into the U.S. Open.
Roddick can beat all seven players ahead of him in the rankings, except Federer.
"I need to get back physically in shape," Roddick told reporters in London. "I don't feel like I've been in shape for a little while. The last time I've been able to train aggressively is probably May."
Based on what we saw this season, is it going to be primarily a two-man show in 2011?
Yes. Murray and Djokovic haven't made sufficient progress to narrow the margin. When you think Djokovic is about to pick it up again, showing form similar to early 2008, he disappoints. How much higher can Soderling go? Tomas Berdych has all the weapons to threaten the duo, but can he do it consistently at majors?
When Federer was asked if the gap between the big two and the rest had grown, he said, "Possibly."
He was being polite.
The danger man for the duo is Juan Martin del Potro, but his wrist injury has complicated matters.
Who is due for a breakout season?
Call it slim pickings if we're seeking a player outside the top 20 who can crack the top 10, aside from veterans who have been around -- such as Nikolay Davydenko and David Nalbandian, and a returning del Potro.
On talent, Ernests Gulbis is always a candidate. However, at this point, the desire appears to be lacking.
Watch out for Andrey Golubev. The 23-year-old, who was born in Russia, represents Kazakhstan and spends most of his time in Italy, has a sizable forehand and a nice one-handed backhand. He has power in his legs. Golubev is ranked 36th, after ending 2009 at 133rd.
Ravi Ubha is a frequent contributor to ESPN.com.