Earlier the two players had tied on 274, 14-under-par, for the 72 holes of regulation play with Garcia closing with a 70 and Goosen a 69.
The 23-year-old Spaniard, who earned 1.2 million dollars for the victory, thus ends a win-less spell which saw him drop from 25 places in the world rankings from number six to number 31.
Garcia beat Goosen’s compatriot Ernie Els on the same play-off hole, the par-three 16th, two years ago when he chipped in for a birdie.
On that occasion he picked up two million dollars in prize money as it was a smaller field of 12 — as opposed to 18 this year — with the same total purse.
On Sunday Goosen picked up US$500,000 as runner-up.
Vijay Singh of Fiji finished third on 277 after a 69 to earn $400,000.
Northern Ireland’s Darren Clarke had the best round of the day, a 67 for 278, to finish fourth to pick up $300,000.
Defending champion Ernie Els, who came into this tournament chasing his fourth win in three years, closed with a respectable three-under-par 69 in spite of a bogey at the last to finish on 290.
Leading final round scores:
274 — Sergio Garcia (Spain) 68, 66, 70, 70; Retief Goosen (South Africa) 70, 67, 68, 69. Garcia won at first extra hole.
277 — Vijay Singh (Fiji) 65, 72, 71, 69.
278 — Darren Clarke (Northern Ireland) 66, 71, 74, 67.
281 — Jerry Kelly (United States) 67, 67, 76, 71; Kenny Perry (US) 65, 68, 73, 75.
282 — Adam Scott (Australia) 66, 74, 74, 68; Chris DiMarco (US) 66, 71, 74, 71.
284 — Stuart Appleby (Australia) 67, 75, 70, 72.
285 — Fred Funk (US) 71, 71, 71, 72; Tim Clark (South Africa) 68, 71, 73, 73; Jay Haas (US) 70, 72, 71, 72.
286 — Padraig Harrington (Ireland) 72, 70, 74, 70.
287 — Charles Howell III (US) 73, 67, 75, 72; Robert Allenby (Australia) 66, 78, 69, 74; Stephen Leaney (Australia) 68, 72, 70, 77.
290 — Ernie Els (South Africa) 72, 75, 74, 69.
292 — Nick Price (Zimbabwe) 69, 75, 75, 73.—AFP/Reuters