Will Djoker, Woz pass Canada crucible?

The U.S. Open Series began in mid-July, but this week's virtually combined event in Montreal and Toronto is the unofficial curtain raiser.

A slew of withdrawals won't really hurt the men's tournament, since the big three arrived unscathed in Quebec. It's a stacked field in Ontario, with the entire top 20 present.

How do the draws look? If things go according to plan, three third-round blockbusters beckon.


First quarter: Work for Nole

A nice, easy start for Novak Djokovic as the new world No. 1, eh? Not really. Djokovic has a supremely tough section.

His first opponent could be Nikolay Davydenko, for years a regular in the top 10. Davydenko is slumping, although he gets a qualifier in the first round and can get hot at any time. Isn't he due for a resurgence?

If Djokovic reaches the third round, Juan Martin del Potro likely awaits in a heavyweight tussle. Their French Open encounter was close (won by Nole), and this is the Argentine's favorite stretch of the season. Given the Latin presence in Montreal, we'd guess del Potro would have the fans on his side.

The highest seed in Djokovic's quarter is No. 5 Gael Monfils, and he'd be a much gentler foe in the last eight than either John Isner or Marcos Baghdatis.

Second quarter: Roger's revenge?

Djokovic competes at a tournament as the No. 1 for the first time, and Roger Federer begins life as a 30-year-old Monday. Federer's opening match at the Rogers Cup last year came against the man he's likely to face this edition, Juan Ignacio Chela, another member of the 30-plus club.

Just as in 2010, it should be comfortable for the Swiss.

The highlight comes in the third round, when Federer is expected to face Jo-Wilfried Tsonga. Their rivalry intensified after the Frenchman's rally from two sets down at Wimbledon. And don't forget in Montreal two years ago, Tsonga downed Federer by coming back from a 5-1 third-set deficit.

Tsonga's rejuvenated countryman, Richard Gasquet, also victorious against Federer in 2011, looms in the quarterfinals.

Third quarter: Ernie's opportunity

It's a good thing organizers gave Ernests Gulbis a wild card. He's compelling to watch, whether it's pummeling his serve and forehand or going walkabout for a few games. Apparently, officials were deliberating between Gulbis and Lleyton Hewitt, as predictable as the Latvian is unpredictable.

Gulbis is finally in form, having won in Los Angeles, and a repeat of the L.A. final is a possibility in the third round. However, before sixth seed Mardy Fish can get there, he'd likely need to overcome Feliciano Lopez. Lopez inflicted a demoralizing loss in their Davis Cup duel last month, prevailing 8-6 in the fifth.

But Fish has already made progress at the tournament, without hitting a ball. A bye means he's into the second round for the first time.

There's little to trouble two-time defending champion Andy Murray until the quarters: Stanislas Wawrinka has regressed, and David Nalbandian, following numerous surgeries, is a shadow of his former self.

Fourth quarter: Gentle for Rafa

Rafael Nadal wants another crack at Djokovic, who has beaten him all five times they've squared off in 2011. Rafa's not the type to back down.

Going deep in Montreal shouldn't be a problem. Nadal has an unthreatening, shall we say, start, pitted against either Jeremy Chardy or Ivan Dodig. Looking ahead, Nadal now handles the likes of Tomas Berdych, Gilles Simon and Fernando Verdasco comfortably, so a spot in the final four is pretty much assured.

Semifinal predictions: Djokovic defeats Gasquet; Murray defeats Nadal

Winner: Djokovic


First quarter: Difficult for Caro

Always making the news, that Caroline Wozniacki. Wozniacki, unusually for her, hasn't played in a while, but the romance rumors with Rory McIlroy have kept the world No. 1 firmly in the spotlight.

There's a good possibility for an early exit in Toronto. Wozniacki's potential second, third and quarterfinal opponents are Yanina Wickmayer, Dominika Cibulkova and French Open champion Li Na. Nerves got the better of Wickmayer when the Belgian had Wozniacki on the ropes in Charleston this spring, and Cibulkova is 2-1 versus Wozniacki this year. However, Wickmayer and Cibulkova might not be 100 percent.

The marquee first-round matchup was supposed to be Venus Williams versus Ana Ivanovic, but Williams withdrew because of a viral illness.

Second quarter: All down to Petra

Petra Kvitova is hoping her immediate post-Wimbledon future is better this year than last. After reaching the semis in 2010, Kvitova lost five straight. Now the reigning Wimbledon queen, the shy Czech must shoulder the weight of expectation and perform under even more scrutiny.

Kvitova is tested straightaway, against either Sara Errani or Anabel Medina Garrigues. They're scrappers who get every ball back and thus force opponents to hit one extra shot, so if Kvitova's mind isn't fully on the job, watch out. If it is, it'll be routine.

If the seventh seed is on her game in general, she'll be hard to stop.

Third quarter: Maria, meet Marion

It wasn't a major, but make no mistake, Maria Sharapova's crushing loss to Serena Williams in Stanford in late July had to sting.

Sharapova crumbled in another important test, those double faults popping up yet again.

The Russian is back in Toronto and faces danger in a probable third-round clash against Marion Bartoli. (Is Bartoli becoming a sentimental favorite?)

Bartoli is one of the finest returners in the game, and that may throw off Sharapova mentally, leading to more double faults. For the record, Sharapova leads their head-to-heads 4-0, not conceding a set; she no doubt likes returning the Bartoli serve. But Bartoli is playing the best tennis of her career.

Victoria Azarenka, the now chilled fourth seed, tries to rebound from an unexpected loss to Marina Erakovic in Stanford.

Fourth quarter: Serena versus Kimmy?

Out of action most of the past four months, the last thing Kim Clijsters wanted was a tricky opener. She was accommodated, drawing a qualifier after a bye.

However, the second seed will go from one extreme to another in the third round, as she's expected to confront Serena Williams in what would be their first tussle since the match of infamy at the 2009 U.S. Open. A little more match practice would have helped Clijsters heading in.

Serena, in good shape, cruised to the title in Stanford, playing big, controlled tennis from the baseline, ripping returns and winning a hefty amount of points behind her first serve. As such, the 13-time Grand Slam winner should ease past former No. 1 Jelena Jankovic if they tangle in Round 2.

Semifinal predictions: Kvitova defeats Li; Serena Williams defeats Bartoli

Winner: Williams

London-based Ravi Ubha covers soccer and tennis for ESPN.com. You can follow him on Twitter.