ESPN Tennis

The weather on the men's side of the U.S. Open Series is hot from the get-go, but now we enter the weeks when at last the fields are equally sizzling. After so-so fields and lightweight drama in Los Angeles, Indianapolis and Washington D.C., ATP Masters Series events in Montreal and Cincinnati over the next two weeks boast deep entry lists and many potentially rich plot lines.

Most of all, the men who stand head and shoulders above all others, Roger Federer and Rafael Nadal, have arrived in North America. Here's a look at where things stand with several notables hoping to make a splash at these tournaments as they seek to build traction for the U.S. Open:

Roger Federer
When he won his first Wimbledon four years ago, Federer opted to compete the next week in his homeland, receiving the gift of a Swiss cow and grinding his way to the finals of a clay-court tournament.

The days of milk and fondue (Federer's favorite guilty pleasure food) are over. Unlike sports like baseball, basketball and football, in a year-round sport like tennis a competitor must carve out his offseason. It's been a month since Federer last played. Will he be rusty? Eager? Check out Federer's last three Canada-Cincy efforts: In '04 he won Toronto and lost in the first round of Cincy; in '05 he didn't even play in Canada, but went on to win Cincy; and last year he won Toronto and then lost a desultory second-round match to Andy Murray. Each of those years he won the U.S. Open. This man knows pacing quite well. Though it's tempting to wonder what new tricks Federer might bring to the table as he pursues tennis immortality, as ESPN's Cliff Drysdale said, "What more can you give the man who has it all?"

Rafael Nadal
Rather than skip the entire month between Wimbledon and this week -- as he did in 2006 -- Nadal opted to play a clay-court event in Stuttgart, Germany. Even if Stuttgart wasn't on hard courts, perhaps the match play Nadal gained from winning on his best surface will sharpen his knife as he seeks to make a genuine go at the U.S. Open. While it's hard to imagine what Federer can add to his portfolio, Nadal is on a happy acquisition spree. As U.S. Davis Cup captain and ESPN analyst Patrick McEnroe said, "He's always looking for ways to make himself better, never satisfied with what he's done." Everything from Nadal's serve to volleys to slice backhand has been enhanced.

Novak Djokovic
Having firmly established himself as 2007's third-best by reaching semis in Paris and London, crisp and hungry 20-year-old enters level of significant expectation, where a win at one of the next events will show much -- and anything less than at least one semi is disappointing. Says John McEnroe: "I definitely put him ahead of Roddick." Excessive ball-bouncing before serving raises scintilla about gamesmanship.

Andy Roddick
He didn't beat a player ranked higher than 38th on his way to winning D.C. last week, but as Roddick said, "We still have three weeks in between [now and the U.S. Open], so a lot can happen between now and then. But I put myself in a good position for next week. It's definitely not going to hurt."

Still, since joining forces with Jimmy Connors a year ago, properly ascertaining Roddick's value has been tricky. Were losses to Federer at the '06 U.S. Open final and '07 Australian Open semis signs of eternal distance? What's his tactical vision for beating Nadal? Did his Wimbledon loss to Richard Gasquet show that he's closer to the middle of the top 10 than the very top? Or can Roddick reassert his skills and bolster his weaknesses? Roddick's already learned much from Connors on how to better build points. Now he'll also ape Connors' career arc by using the U.S. Open as the place for staking his claim to greatness.

Richard Gasquet
His Wimbledon semifinal run was a breakthrough. It's about time for him to step up and prove he's a man for all surfaces by grinding his way to wins on hard courts rather than merely dazzling with flurries of shotmaking.

The Pack: Wolves or Sheep?

Dmitry Tursunov, Radek Stepanek: They're the pair of impish semi-late bloomers currently tied for second in the U.S. Open Series points standings. Tursunov is physical enough to step into higher gear, although he did lose in the first round in Montreal to Nicolas Kiefer. Stepanek's eclectic prowess can disrupt -- but not disturb -- tennis' higher powers.

James Blake: He authored a fine book, but is encountering writer's block in finding the tennis that took him to the top 10.

Lleyton Hewitt: His intensity and quality tennis at Paris and London, coupled with bringing legendary coach and fellow Aussie Tony Roche into his camp, shows he's priming for a big push on hard courts over the next two summers -- that is, here in the U.S. and the '08 Australian. It still takes a quality stake to drive through his heart.

Sam Querrey: He floundered through the first half of the year but bailed out his summer and balance of '07 with run to Indy semis, highlighted by his win over Blake.

John Isner: His massive size and serve saw the '07 NCAA singles finalist soar from 416 to 190 on the heels of reaching D.C. finals. He won a record five straight matches in third-set tiebreaks. He was granted a wild card into Cincinnati, so let's see if this summer's Cinderella remains the belle of the ball rather than turns into a pumpkin.

Nikolay Davydenko: The grim Russian warrior has already played 21 tournaments -- including four post-Wimbledon clay-court events -- and is now under a cloud amid a betting scandal.

Tommy Robredo: For all notions that the Spanish grinder is strictly a dirtballer, he's twice been to the Cincy semis and four times advanced to the last 16 at the U.S. Open. Were an American man to do that well on European clay, he'd be coronated.

Andy Murray: Don't expect much as he attempts to recover from wrist injury. Murray's return in Montreal will be his first match in almost three months.

Joel Drucker is based in Oakland, Calif., and writes about tennis for Tennis Magazine and The Tennis Channel.