LONDON -- With the top defensive players increasingly getting the better of him often in recent years, Roger Federer would like to speed up the game of tennis.

Or at least the courts the matches are played on.  
Federer lost to Novak Djokovic in the final of the season-ending ATP finals on Monday, and then praised the top-ranked Serb's ability to retrieve so many shots and keep the ball in play. That's a trait Djokovic shares with Federer's other two biggest rivals -- Rafael Nadal and Andy Murray -- and the Swiss star said attacking play doesn't always reap the benefits it deserves even on hard courts because they're often slower than they used to be.  
"It's an easy fix. Just make quicker courts, then it's hard to defend," Federer said. "Attacking style is more important. It's only on this type of slow courts that you can defend the way we are all doing right now."  
Monday's final at the O2 Arena had a familiar feel to it. Federer did most of the attacking, trying to dictate play with his forehand and aggressive shot making. But Djokovic, as he often does, kept finding ways to get the ball back over the net and was sharper on the key points.  
Federer won the first nine points of the match and was up an early break in both sets, but Djokovic recovered to win 7-6 (6), 7-5.  
Federer was the two-time defending champion in London and emphasized that he was happy with this court, calling it one of the faster indoor surfaces on the circuit. He said slower courts are also good for long rallies -- which are a big crowd pleaser -- but that having more variety in the surfaces would force players to learn to be more aggressive.  
"What you don't want is that you hit 15 great shots and at the end, it ends up in an error," he said. "So I think sometimes quicker courts do help the cause. I think it would help from time to time to move to something a bit faster. That would help to learn, as well, for many different players, different playing styles, to realize that coming to the net is a good thing, it's not a bad thing."  
Federer has won a record-equaling seven Wimbledon titles on grass, the quickest surface, but has only one French Open title on the slower clay, where Nadal has repeatedly thwarted him.  
Djokovic and Murray also rely heavily on their great defensive abilities, which have helped set them apart from the rest of the pack.  
Having more tournaments played on faster surfaces could make it easier for other players to challenge the sport's "Big Four," Federer said, adding that he wasn't sure tournament directors would necessarily buy into that.  
"I think some variety would be nice, some really slow stuff and then some really fast stuff, instead of trying to make everything sort of the same," he said. "You sort of protect the top guys really by doing that because you have the best possible chance to have them in the semis at this point, I think. But should that be the goal? I'm not sure."  
Djokovic said his strategy against Federer is usually to try and extend the rallies and hope for an opportunity.  
"He's somebody that is very aggressive, that likes to finish points very quickly," Djokovic said. "But I managed to get a lot of shots back into the court, being passive, a couple meters behind the baseline. ... That was one of the goals tonight, to always try to get him into the longer rallies where I think I had the better chance."