Rublev's remarkable rise by numbers
Top seed Djokovic outplayed Swedish youngster Mikael Ymer as Tsitsipas and Rublev battle from two sets down
World No.1 Novak Djokovic improved to a stunning 32-1 win-loss for the season as he swiftly advanced to the Roland-Garros second round with a routine 6-0, 6-2, 6-3 performance against Sweden's Mikael Ymer.
The Serb, who is gunning for an 18th Grand Slam title this fortnight, and a second in Paris, needed just over an hour and a half to sidestep the 22-year-old Ymer, and will next face Lithuanian Ricardas Berankis for a place in the third round.
It was Djokovic's first Grand Slam match since his shock disqualification at the US Open for accidentally hitting a line judge with a ball.
The 33-year-old has since lifted the trophy at the Rome Masters and comes to Roland-Garros as a top contender threatening the reign of 12-time champion Rafael Nadal.
Earlier on Court Philippe-Chatrier, home favourite Kristina Mladenovic blew a 5-1 lead en route to a 7-5, 6-3 defeat to Germany's Laura Siegemund.
A double-bounce call on set point for Mladenovic was not made by the umpire and the Frenchwoman admits it affected her moving forward.
"Obviously that double bounce, it was set point, supposed to be 6-1, and I think the chair umpire was the only person not to have seen it on the centre court," said Mladenovic.
"So we can call that a turning point. I should have been 6-1. I don't know about the outcome of the rest of the match after that, but, yeah, was definitely a key point.
"It did affect me. I really tried to stay calm, though, and not try to complain much, because it was a brief complaint, because in these kind of situations, you know that they are bad, they made a mistake, there is nothing you can do about it. Just have to try to refocus and keep going. I had the results still in my hands, but you see how tennis, it's about one point at times. And I got to give her credit for going for her shots afterwards and slowly coming back."
Former Roland-Garros junior champion Ons Jabeur fought back from a set down to eliminate Kazakhstan's Zarina Diyas 4-6, 6-3, 6-1.
The Tunisian No.30 seed is through to the second round in Paris for the first time since 2017 and will next tackle Japan's Nao Hibino.
Canadian Denis Shapovalov, who cracked the top 10 for the first time last week, punched his ticket to the last 64 with a 6-2, 7-5, 5-7, 6-3 success over French veteran Gilles Simon.
His reward is a clash with Spaniard Roberto Carballes Baena.
Today, both players fell behind two-sets-to-love down in their respective first-round matches at Roland-Garros only to turn things around with a herculean effort and emerge as victors.
Tsitsipas wiped a two-set deficit against a brilliant Jaume Munar 4-6, 2-6, 6-1, 6-4, 6-4 to record his first-ever comeback victory from love-two down.
"I don't think I've ever played a match like this before. The emotions, the nerves at the very beginning were not there. But with slight adjustments, and trying find a way to win a different way. It wasn't working out for me at all in the beginning, nothing was working," said the fifth-seeded Tsitsipas, who next plays Uruguayan Pablo Cuevas.
"I don't think I had a match like this before, everything was not responding. But I'm really proud of myself, the effort that I put and the amount of dedication. Playing a best-of-fiver can be very challenging and I'm really happy that I will walk away from Suzanne-Lenglen today with a W."
Earlier, Russian No.13 seed Rublev also pulled off a comeback from two-sets-to-love down for the first time in his career by hustling his way past Sam Querrey to reach the second round with a 6-7(5), 6-7(4), 7-5, 6-4, 6-3 result.
The 22-year-old will take a 26-6 win-loss record for the season into his next match against Spaniard Alejandro Davidovich Fokina.