The 31-year-old was left in the shade by straight-hitting Czech Lukas Rosol for much of their first-round clash but he did finally come to life to win 4-6 6-1 3-6 6-3 6-4.
It was touch and go for a while, though, as Rosol, who famously beat Rafael Nadal in the Wimbledon second round in 2012, threatened another huge upset.
Wawrinka’s ruddy complexion was deepening early in the fourth set when he faced two break points but Rosol failed to take either and the match swung.
Urging himself on, Swiss Wawrinka, who only arrived in Paris on Saturday having won the warm-up event in Geneva, levelled and broke in the third game of the decider to take control.
Torrential rain delayed the start of day two for two-and-a-half hours, adding to the frustration of Sunday’s weather-hit false start to the year’s second grand slam.
Women’s fourth seed Garbine Muguruza, a tall Spaniard with a Venezuelan mother, clearly did not appreciate the clammy conditions as she struggled past Slovakia’s Anna Karolina Schmiedlova in three sets wearing a long-sleeved top.
It was a day to grind it out, though, and last year’s Wimbledon runner-up proved she has the tenacity as well as the power to have a deep run, winning 3-6 6-3 6-3.
Russian Svetlana Kuznetsova, champion 10 years ago, also progressed, beating Yaroslava Shvedova 4-6 6-1 6-4 on a day in which seeded players generally flourished.
Simona Halep, beaten by the currently suspended Maria Sharapova in the 2014 final, made short work of her opener, dropping only two games against Japan’s Nao Hibino.
Men’s fifth seed Kei Nishikori, a semi-finalist in Madrid and Rome, followed Wawrinka on to Chatrier with his job already half done against Simone Bolelli.
The Japanese carried on where he left off before rain halted play on Sunday, easing to a 6-1 7-5 6-3 victory.
He was joined in the second round by eighth seed Milos Raonic, who had a straight-sets win over Serbia’s Janko Tipsarevic but former top-tenner Grigor Dimitrov bowed out to 22nd seed Viktor Troicki.