Tommy Haas turns back the clock, upsets Novak Djokovic at Key Biscayne

Tommy Haas took advantage of cold temperatures and a renewed confidence to defeat Novak Djokovic in straight sets. (Matthew Stockman/Getty Images)

Tommy Haas pulled off the upset of the 2013 season on Tuesday night, ousting two-time defending champion Novak Djokovic 6-2, 6-4 in the fourth round of the Sony Open.

Just a week shy of his 35th birthday, Haas notched his second career win over a No. 1 player and became the oldest man to defeat a top-ranked player in 30 years. It was the earliest loss for Djokovic at an outdoor hard-court tournament since Olivier Rochus beat him in the first round of Miami in 2010.

Here are three thoughts on Haas' victory:

• Haas used the cold conditions to his advantage: When umpire Mohamed Lahyani comes out on court in a jacket and gloves and the entire Djokovic entourage is wearing puffy, insulated jackets, you know it's cold. The chilly conditions played perfectly into Haas' game plan as he used his backhand slice with tremendous effectiveness and kept Djokovic off balance all night. The conditions meant the balls stayed lower, and with Haas' ability to hit his beautiful one-handed backhand flat down the line, Djokovic was left digging balls out of the court or trying to redirect his pace. The first set was vintage Haas, who hadn't played a match this well in years.

"I had a good game plan," Haas said. "Conditions favored me a little bit with the game that I played against him. It was tough out there with the swirling wind."

Once Haas pocketed the first set easily, Djokovic kicked into survival mode. He was under pressure on almost every service game in the second set and fought off break points with some gutsy serving and with a little help from Haas, who missed badly on some second-serve returns. The match looked like it was going to flip midway through the second set after Djokovic won 11 straight points to get a break back and hold for 3-3. But Haas' confidence, built up over the last year, then came into play. Haas settled down, got the break he needed at 4-4 and then served out the match with ease.

• Djokovic played horribly: Not taking anything away from Haas, but it's impossible to ignore the fact that Djokovic was beyond bad. He hit 30 unforced errors to just seven winners, with 19 of those errors coming off his forehand. Rally after rally broke down thanks to that struggling forehand, and his footwork wasn't sharp all night. Was it the cold conditions? Haas' level? A bad day at the office? Probably all of the above.

"All the credit to him," Djokovic said after the match. "He played a great match and he was the better player, no question about it. The results show everything. It's definitely the worst match I have played in a long time.

"There are days where you just don't feel good on the court. Nothing really goes your way. This is one of those days. But all the credit to him for making me play this bad."

• The feel-good story of the year so far: A year ago, Haas was barely a blip on the radar screen. Ranked No. 145 then, Haas has spent the last year raising his ranking the hard way, at a time when it would have been easy to just call it quits. The talented German, who peaked at No. 2 in 2002, has endured a career defined by ill-timed injuries. But after the birth of his daughter, Valentina, with his wife, actress Sara Foster, Haas wanted nothing more than to be able to compete long enough for Valentina to be able to see him play.

"Somewhere in the middle of last year, sometime in April, May, my body sort of adjusted a lot, got better, and I could train," Haas said. "If you can't train and put in the hard yards in this sport anymore, you're not going to get far.  You know, not at least to the point where maybe you have a chance against a top player. From experience, luckily I know that, and luckily I'm a guy that likes to work out and gets in the best shape that I can possibly can, my body allowing."

Thus began 12 months of playing qualification tournaments to get into draws and battling other journeymen outside of the spotlight. The hard work paid off. He scored four top-10 victories last year and won two titles, including the grass court title in Halle, where he beat Roger Federer in the final in straight sets. By October, he had cracked the top 20. Now he's on the verge of the top 15. Oh, and 2-year-old Valentina has been courtside all week, with pacifier in mouth.

"These are the moments I appreciate the most, going on those big stadiums, big stages, playing against the best people in the world," Haas said. "Playing against something like Novak and coming out on top at this time of my career, it's unbelievable. It goes up as one of my most best wins of my career."