PARIS -- Ah, destiny. It can be a slippery, squirming eel. Those who manage to hold on, despite all the violent twists and turns, are rewarded.
Consider Novak Djokovic, temporarily the world's No. 2-ranked player. Through the course of an increasingly ludicrous win streak that is approaching five months, the 24-year-old Serb has successfully navigated some difficult circumstances. He has beaten Rafael Nadal and Roger Federer no fewer than seven times. He survived a third-set tiebreaker against Andy Murray a few weeks ago in Rome. He has won on four different continents, three different surfaces and in all kinds of atmospheric conditions.
There were four Grand Slam singles titleholders in the main draw here at the French Open, and as luck would have it, Djokovic drew one of them in the third round. Because the once-formidable Juan Martin del Potro is still mounting a comeback after spending eight months sidelined with a wrist injury, his ranking is not yet where it belongs. Still, it was thought he had a fighting chance in this anticipated match when it spilled into a second day. If you are still not quite right -- a hip strain curtailed del Potro's clay-court preparation -- and you are playing the fittest man in the world, wouldn't it be fortuitous if intervening darkness split the match in two?
And yet, Djokovic, who has seen a few eels in his time, endured. He won his 40th consecutive match of the season Saturday with a 6-3, 3-6, 6-3, 6-2 victory over the game -- very game -- del Potro. He now finds himself only three matches from surpassing John McEnroe's Open era record of 42 straight to start a season, set in 1984. Going back to last year's Davis Cup final, Djokovic is 42-0; Guillermo Vilas (46) and Ivan Lendl (44) are the only men who did better.
Lendl has always been a hard-to-please cynic when it comes to today's players. As the winner of eight Grand Slam singles titles, it is his right. He doesn't watch a lot of tennis these days, but he's been following Djokovic very closely. Fifteen minutes after the match, he knew the score.
"The guy is playing phenomenal tennis," said Lendl, who was traveling to his native Czech Republic, from the airport in Vienna, Austria. "He has improved his conditioning, and therefore the mental part of his game, which was his weakness.
"I don't want to call myself a doubter, but I'm starting to believe in this guy. In the Rome final, he took Rafa apart -- he didn't have any answers. It was like picking the cherries off the tree."
Del Potro, who is good friends with Djokovic, had a difficult time describing what happened.
"I not have many words to explain his game," del Potro said. "He has everything, everything perfect. He has very good movement. He's very fast. He improved his serve. He's beating all the players very, very easy -- and I'm one more victim of his game."
On Friday, the match was moved from the center court to Suzanne Lenglen. They started past 7:30 p.m., local time, and split sets and 19 games evenly. There was probably enough light to get in a few more games, but, appropriately, they agreed to leave the match where it was. So for del Potro, it became a much more manageable best-of-three match on Saturday.
In the sixth game of Part II, Djokovic showed some of the tenacity that has surfaced during his streak.
Del Potro had stolen a few points and was sitting on two break points. The first Djokovic erased on a bad bounce (fortunate for him) and the second with a spectacular crosscourt forehand that barely hit del Potro's racket. After holding serve, Djokovic broke del Potro, when the Argentine's hasty, fall-away forehand hit the net. That 4-2 lead gave Djokovic the space he needed.
He finished the decisive frame this way: 1) forcing a backhand error, 2) stroking a forehand winner that even del Potro was moved to applaud, 3) ripping a 122 mph ace down the middle and 4) a fearless forehand that glanced off del Potro's frame.
That was pretty much it.
The fourth set -- a movie we already have seen more than a few times this year -- was predictable. Del Potro, worn down by the effort to hang with the best player in the world, double-faulted on break point to give Djokovic a decisive lead. The last shot -- a gorgeous, disguised drop shot from the backhand side -- was so sweet it made your teeth ache.
"Hopefully," del Potro said, "he's ready to be No. 1 very soon. Today he was much better than me. He can win the tournament. Rafa can win the tournament, Federer, Murray.
"But [Djokovic] is playing really, really good. I enjoy playing against him, because he's making records every day, so maybe he will be in the history of this sport."
Greg Garber is a senior writer for ESPN.com.