After falling short in a playoff on three occasions this season, Garcia finally broke through at Real Club Valderrama on Sunday to secure his first professional win since the 2020 Sanderson Farms Championship.
Garcia recorded a five-under-par 66 during the third round to chip into the four-stroke advantage of overnight leader Lahiri, who missed a three-foot putt on No.18 and limped to a 73. Garcia then rolled in a short putt in the playoff to secure the win and pocket $4 million ($A5.9 million) for his first-place finish.
Garcia was asked if winning in Spain on his favourite course served as one of the highlights of his career.
"Without a doubt," he said.
"Not only that, but also Carlos winning. Alcaraz won today (at Wimbledon). Hopefully Spain wins tonight (versus England in the Euro 2024 Championship). It would be an unbelievable weekend.
"Actually I was talking to my wife, my manager, and I was like, shooting five-under and I'll see what happens. But played well, played well in the playoff. It's just a tough hole. But so happy."
POV: — LIV Golf (@livgolf_league) @TheSergioGarcia's first LIV Golf winning moment �#LIVGolf @fireballsgc_ pic.twitter.com/jR0WRJvmKcJuly 14, 2024
Garcia, who ended up at five-under 208 for the tournament, also saw Fireballs GC edge Crushers GC in a playoff to win the team competition. Abraham Ancer and David Puig defeated Crushers GC captain Bryson DeChambeau and Paul Casey on the first playoff hole for the $3 million ($A4.4 million) team prize.
Lahiri walked away with a second-prize payday of $2.25 million ($A3.32 million) while England's Tyrell Hatton (69) finished in third at four under and American Patrick Reed (67) and South African Louis Oosthuizen (69) joint-fourth at three under.
"Yeah, I felt pretty gutted for Lahiri," Hatton said.
"It was a bit awkward on the 18th green with the crowd because they wanted Sergio to win. Yeah, I mean, I think everyone thought it would be done there, and unfortunately for Lahiri and the Crushers, they ended up having to go into a playoff.
"That's definitely going to sting a lot for those guys. From my point of view, nice to have another good week going into the Open."
Cameron Smith (68) was in a tie for sixth at two under, while fellow Australians Marc Leishman (71) finished even, Lucas Herbert (70) seven over and Matt Jones (73) 12 over.