The Spaniard has had a torrid time with injury since signing for the French giants.
Ramos has had a hard time shaking off a leg problem, an injury he sustained in May.
He returned to the bench against Manchester City in midweek but was an unused substitute.
Despite a lack of game time, Mauricio Pochettino threw him in at the deep end as he trusted him from the start against Saint-Etienne at Geoffroy Stadium.
There may have been concerns that Ramos was not the same player he once was.
After all, he has been out of action for half-a-year and, at 35 years old, he's no spring chicken.
But he proved that he's still got it with a composed performance on his PSG debut.
Ramos played the full 90 minutes as PSG prevailed 3-1.
Saint Etienne took the lead in the 23rd minute, but goals from Marquinhos (2) and Angel Di Maria meant Ramos' debut was a winning one.
His highlights from the game have been compiled by YouTube user SVMM and you can watch them below:
Pochettino was pleased that Ramos finally made his PSG debut.
"I am very happy for Sergio, we are all happy that he is here after a few months without having been able to play since his signing at Paris Saint-Germain," he said after the game, per Goal.
"It's the biggest step for him, having played 90 minutes today."
Football fans were very impressed by Ramos' performance on his return. View some of the reaction below...
SofaScore gave Ramos a rating of 7.2/10.
He completed 94% of his passes (95), made two interceptions, made three tackles and won five duels.
It was a good performance from Ramos on his return. He's only going to get better as he gets more minutes under his belt, too.
Ramos performed at a high level on Sunday but if he does get back to his very best, PSG are going to be even scarier than they currently are.News Now - Sport News