The 22-year-old escaped the inferno which wrecked a players' hotel in the French city of Bordeaux just two weeks ago where he was taking part in a second-tier Challenger event.
The fire, which began in his room, also left him virtually penniless and with just the clothes he was standing in.
His passport, equipment and laptop were all destroyed but he was lucky to escape uninjured as he had just left his room to drop off racquets to be restrung and to have some playing gear laundered.
The fire also claimed his winner's cheque of 4,300 euros (6,700 US dollars) from the previous week's tournament in Rome.
"I was having breakfast in the hotel on Monday morning, which is situated in the basement, when I heard about the fire," said the world number 74 who beat 1998 champion Moya 7-6 (7/4), 6-2, 6-7 (1/7), 4-6, 6-3 in a gruelling four-hour clash on Sunday.
His win, a first in a Grand Slam event, followed three gruelling qualifying rounds here last week.
"When the fire happened, it was a national holiday in France, so I had no chance of buying any clothes.
"All I had was two tennis racquets, one pair of tennis shoes and two t-shirts to my name. I received a couple of polo shirts for my first match and by the Tuesday afternoon new clothes had fortunately arrived from two Argentinean friends."
Schwank, one of 15 Argentinians in the first round draw at Roland Garros, said he is now fighting a legal battle after he was reportedly accused of being responsible for the blaze by leaving an oven switched on in his room.
It's a charge he vehemently denies.
"We have a lawyer managing all of this. I spent that whole day in the police station," he said.
"These are not things that I do on a daily basis and you have to learn to cope with the situation as quickly as possible."
Incredibly, and despite the fire, Schwank went onto win the Bordeaux tournament, picking up a useful 12,500 euros (19,700 US dollars) in the process.
It was his third successive Challenger tournament success to add to titles in Rome and Cremona.
"Everything happens for a reason. I managed to cope with everything and that's important."
Schwank, whose family originated in the German-speaking part of Switzerland, overcame serious cramps in his win over Moya.
Now he has at least two days to recover before he tackles either Spain's Marcel Granollers or Michael Berrer of Germany for a place in the third round.
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