Rafael Nadal is safely through to round two after a four-set battle with Argentine debutant Francisco Cerundolo.
The Spaniard, who is on course for a calendar grand slam following his wins at the Australian and French Opens earlier this year, won 6-4 6-3 3-6 6-4.
It was a successful return for Nadal, 36, just three weeks after he underwent make-or-break treatment on a chronic foot injury. He looked to be motoring through the match until a series of unforced errors allowed Cerundolo, 23, back in.
The Argentine upped the tempo and used his booming forehand to overpower twice Wimbledon champion Nadal, who has won 20 other Grand Slam titles, taking the third set and breaking serve in the fourth.
But Nadal, who won the Australian Open in January and the French Open earlier this month, regrouped and used all his experience to fight back, breaking a now nervy opponent twice to seal the match to the delight of a packed Centre Court.
"After three years of not playing here I'm very happy to be back," he said afterwards.
"The last three years I didn't put a foot on a grass court, so it always takes a while in my first match. Every day is a test and this was an important test.
"At the beginning of the tournament and under the circumstances I arrived here, the victory is the most important thing.
"Everyone knows I had to do some things on my foot, but the most important thing is I am in Wimbledon 2022 and I won my first match!"
Nick Kyrgios came through a five-set first-round thriller against British wildcard Paul Jubb as his fearsome serve, including 30 aces, eventually overpowered the 22-year-old 3-6 6-1 7-5 6-7(3) 7-5.
It was an unexpectedly testing examination for Kyrgios as the outsider kept his cool in the face of the Australian's usual verbal antics, but fell just short. The winner looked pretty flat in losing the opening set to a player whose career highlight was winning the US NCAA college title in 2019, and in his frustration he hammered a ball high and out of Court Three.
Kyrgios is a player the word "chuntering" was invented for as he seems to need to keep up a running monologue to get himself motivated.
He took great offence at a single fan uttering an almost polite boo, complaining to the umpire "You don't accept a hat with two logos on but you accept disrespect of an athlete?"
Kyrgios then complained about a line judge "reporting him" to the umpire. "Not one person has come here today to hear her speak," he said.
The chat appeared to energise him as he began to find his range in a strong second set but Jubb refused to lie down, being edged out in the third and going toe to toe to take the fourth on the back of a strong tiebreak. The Briton, in only his second Wimbledon appearance having lost in the first round three years ago, was ice-cool in ignoring any potential distraction from Kyrgios's running commentary, which included another extended whinge over a non-signalled net cord in the tiebreak.
It is now eight years since Kyrgios stunned then world number one Rafa Nadal to reach the Wimbledon quarter-finals but he has never matched that since and has reached only one other Grand Slam quarter – in Australia in 2015.
The 27-year-old has slipped to world number 40 but his serve remains out of the top drawer, demonstrated when he ripped through the third game of the deciding set to love in 43 seconds before breaking Jubb.
When serving for the set, however, Kyrgios stood back to admire a drop shot, only to be left stranded when Jubb brilliantly ran it down en route to his own break back.
Jubb then failed to convert a break point and, serving to take the match to a decisive tie-break, leaked a couple of shots wide to help Kyrgios secure victory.
British number two Dan Evans crashed out in the first round in a surprise straight sets loss to Australian Jason Kubler.
Evans, seeded 28th, does not have a happy record at Wimbledon and that continued with a 6-1 6-4 6-3 loss to the Australian.
Wild card Alastair Gray pulled off a remarkable straight-sets victory on his grand slam singles debut to reach the second round.
Gray, ranked 288 in the world, saw off 2018 Wimbledon boys' singles champion Tseng Chun-hsin 6-3 6-3 7-6 (3) with a composed display on Court 14.
The 24-year-old from Twickenham, who attended the same US college as British number one Cameron Norrie, took the third set on a tie-break to potentially set up a clash with 11th seed Taylor Fritz in the next round.
