PARIS (AP) So, Stan Wawrinka was asked, were you aware that in the long history of the French Open, no defending champion ever had lost in the first round?
''No,'' Wawrinka replied quickly, his arms crossed, the hint of a smirk on his scruffy face. After waiting a comedic beat, he added with a chuckle: ''And it's still not the case, so it's good.''
Sure, by then, it was easy for the 2015 champion at Roland Garros to kid around, because he barely avoided making the sort of history no athlete would embrace. Eventually warming up on a gray, chilly afternoon, and twice coming back from a set down, Wawrinka edged 59th-ranked Lukas Rosol of the Czech Republic 4-6, 6-1, 3-6, 6-3, 6-4 on Monday to sneak into the second round.
''I know that physically I'm stronger than he is, and I knew that he was going to decline a little bit,'' said the No. 3-seeded Wawrinka said. ''That's exactly what happened.''
Something similar transpired several hours later, when No. 2 Andy Murray faced an even greater deficit, dropping the first two sets against 128th-ranked qualifier Radek Stepanek, who at 37 is the oldest man in the field. Their match didn't finish, though, suspended until Tuesday because of darkness.
After the net-charging Stepanek raced to a 6-3, 6-3 lead, his legs began to falter, and Murray started to work his way back into the match.
The two-time major champion took the third set 6-0, and was up a break at 4-2 in the fourth when they stopped. As dusk began to arrive - there are no artificial lights at Roland Garros - Murray accused his opponent of gamesmanship, complaining to the chair umpire that Stepanek was trying to delay the proceedings.
''How many things can he do to slow the play down?'' Murray said after Stepanek headed to the locker room following the third set. He added: ''Keep an eye on how long this toilet break is.''
After returning to the court, Stepanek changed shirts, drawing a warning for wasting time.
If he was hoping to force the match to another day, it worked. The way he and Rosol challenged two of the top three seeded men was emblematic of the way Day 2 went.
There were no bracket-busting stunners, but the surprises included 2014 U.S. Open champion Marin Cilic's 7-6 (4), 3-6, 6-4, 6-2 loss to 166th-ranked qualifier Marco Trungelliti of Argentina. Four seeded women exited, most notably No. 7 Roberta Vinci, the Italian who ended Serena Williams' Grand Slam bid at last year's U.S. Open.
While Stepanek can rest and regroup, Rosol had no such opportunity to gather himself as he unraveled.
The key moment came with Wawrinka trailing 15-40 while serving at 2-all in the fourth set. Wawrinka saved both of those break points - Rosol helped matters by missing two backhands - and never faced another the rest of the way.
''He (started) to be a little bit tight,'' Wawrinka noted.
The temperature was in the 50s (about 15 degrees Celsius) and rain delayed the start for roughly 2 1/2 hours, conditions favoring Rosol. Early on, nothing went Wawrinka's way. Even his terrific backhand was problematic, including one shank that ended the third set. In all, Wawrinka made 46 unforced errors, 17 on the backhand side.
This should have been easier for him.
Wawrinka is a two-time Grand Slam title winner; Rosol never has made it past the third round in 20 major tournaments and is 110-137 in tour-level matches. His most noteworthy accomplishment was defeating Rafael Nadal at Wimbledon in 2012, displaying the same go-for-broke, flat groundstrokes and intimidating serve he used to such great effect against Wawrinka.
Wawrinka and Rosol played four times previously, with Wawrinka winning each one, most recently Friday at Geneva.
''I wanted ... payback,'' Rosol said.
Monday's match was at Court Philippe Chatrier, where Wawrinka's nearly perfect performance beat Novak Djokovic in the 2015 final. That day, Wawrinka produced what he called ''certainly one of the best matches of my career - if not the best.''
His play was a far cry from that against Rosol in the first and third sets, when Wawrinka produced more than half of his unforced errors. But he eventually turned things in his favor.
Asked what emotions he felt returning to the site for the first time since holding the trophy, Wawrinka said he didn't let those ''great'' feelings linger.
''I came back to play a match,'' he said, ''not to enjoy and think about what I did last year.''
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