PARIS -- It's a cliff-hanger.
Novak Djokovic and Juan Martin del Potro were stopped overnight perfectly poised at a set apiece. A string of long matches on Court Philippe Chatrier had pushed the schedule back, leaving the day's most anticipated match to be shifted to Court Suzanne Lenglen. Spectators rushed to grab seats for this unexpected bonus on the second show court, still milling about in the chill as play began.
Djokovic began looking like the player who hasn't lost a match all year, returning del Potro's early blows with interest and making the big Argentine look slow. But del Potro then showed why he was considered the future of the game before his wrist problems last year, stepping up and tying the match before it was called due to darkness.
Both players will have a lot to think about overnight before coming back to play two or three sets on Saturday. Who does the delay benefit? It was del Potro who called for play to be stopped after winning the second set, saying only 10 more minutes of play would be possible. They will resume third on court Saturday, and if conditions are warmer (as they should be), the faster court should help del Potro. He will also have an extra night's rest to recover, and mentally he will come in with more confidence, knowing he can keep up with the Serb despite his rust. But Djokovic will not let go of his 41-match winning streak easily and can plan strategy overnight with his coach.
Part I told us one thing: This is a match. Part II continues Saturday.
It's time to start paying attention to Roger Federer: He's cruised through his first three rounds, playing beautifully. Things will only get tougher from here, but he's done his job so far.
"I'm at peace with my game right now," he said after dispatching a potentially tricky Janko Tipsarevic in straight sets. "I'm physically fine. I think I had a good preparation, so there's no reason to go crazy right now. I mean, it's still early in the tournament, and also not to be overrated, but at the same time it's really nice to be moving in the draw so well so quickly, really."
No matter what he ends up doing this fortnight, you don't want to miss him in full flight.
There'll be an unexpected women's champion, but not necessarily a new one: For the second straight day, there were upheavals on the women's side as last year's finalist Samantha Stosur fizzled out against a steady Gisela Dulko in three sets on Friday, followed by No. 1 Caroline Wozniacki getting demolished by Daniela Hantuchova. Even defending champion Francesca Schiavone was down a break early but then caught a break when illness caused opponent Peng Shuai to retire.
A day earlier, Kim Clijsters exited after holding match points twice in the second set and was nearly joined by Maria Sharapova. Those four were arguably the top favorites for the title, and all but one are gone before the fourth round. Sharapova did survive, but being pushed to the brink of defeat by a 17-year-old did not inspire confidence for the rest of her campaign.
But while others are sliding, one player seems to be on the upswing: 2009 champ Svetlana Kuznetsova rolled through her match against inexperienced but talented Canadian Rebecca Marino in 49 minutes and recently added 2004 champ Anastasia Myskina to her team.
Ironically, Kuznetsova held match points against Myskina at the 2004 French Open before Myskina eventually went on to win the event.
"She was very smart on the court, so I think I can learn it from her," Kuznetsova said.
Kuznetsova has struggled ever since losing a four-hour epic against Schiavone at the Australian Open, but there are few players whose game is as well-suited to the clay as hers.
Wozniacki needs to reassess: Her loss to Hantuchova underscored the constant critique of Wozniacki's game -- too much defense. She hit just eight winners -- none at all in the first set -- falling 6-1, 6-3 against a very capable but not frightening player. It stirred up all the usual questions about why she's No. 1, when she'll win a Slam and whether she has the game to match up against the biggest guns. She wants it all to stop, but will some tough choices be required?
Wozniacki works hard, plays a lot and likes to keep busy off the court as well, but that leaves limited time for developing her game.
"There's one thing about tactics, there's one thing about mindset, there's also the technical side. Because she plays a lot and gets far, it's very difficult to work on technique, very difficult," said adidas coach Sven Groeneveld, who often works with Wozniacki.
The French are getting tough: Famous for imploding in front of the home crowds, French players showed strong nerves in winning some tight contests. Marion Bartoli clawed her way back against an in-form Julia Goerges, taking a 22-point game en route to a 3-6, 6-2, 6-4 win. Richard Gasquet seems to have undergone a transformation, fist-pumping and fighting his way past a dangerous Thomaz Bellucci 6-2, 6-3, 3-6, 6-3. For once, Gael Monfils didn't make things tougher than they had to be, moving on in three sets. Jo-Wilfried Tsonga did melt down, though, losing a two-sets-and-a-break lead in a 4-6, 6-7 (3), 7-6 (5), 6-2, 6-3 loss to Stanislas Wawrinka.
The guys will need all their new nerve in their next contests -- Monfils faces David Ferrer and Gasquet will face the winner of the match between Djokovic and del Potro.
Kamakshi Tandon is a freelance tennis writer for ESPN.com. Information from ESPN.com's Ravi Ubha contributed to this report.