WENTWORTH, United Kingdom, May 26, 2013 (AFP) - Manassero won a sudden death play-off against England's Simon Khan and Scotland's Marc Warren after the trio had finished level on 278, ten-under par.
Warren exited on the first extra hole and Manassero needed three more holes to shake off the challenge of Khan, the winner here in 2010 which he finally did with a birdie on the par-5, 18th which was played four times.
Aged 20 years and 37 days, Manassero beat Bernard Gallacher's record as the youngest victor in the European Tour's flagship event.
Gallacher was 20 years and 97 days old when he won in 1969.
It was Manassero's first tour win since the 2012 Singapore Open and this was the first three-man play-off in the event since 1976.
Warren's ball was unplayable in the trees to the right of the par-5 18th, the first extra hole, and the Scot was out of contention when his fourth shot ended up in the water beyond the green.
Khan and Manassero both made birdie fours and headed back to the 18th tee from where they both made pars before making birdies, both from bunkers, at the third time of asking.
But Khan's second shot on the fourth playoff hole landed in the creek in front of the green and Manassero's two-putt birdie gave him the biggest win of his career.
Khan had not played on tour for eight weeks because his wife has been unwell but he made light of his lack of golf to shoot a bogey-free 66, the best score of the day to post a total of 278 ten-under par for the rest of the field to shoot at.
Manassero and Warren both had chances to win it in regulation play but missed putts of about 20 feet on the 18th to send them into extra holes along with Khan who had come from off the pace with a 66.
Khan was five shots off the lead at the start of play and his last day performance almost mirrored his efforts in 2010 when he came from seven back to land the title.
English Tour rookie Eddie Pepperell had an impressive first appearance here finishing on eight-under par for a share of sixth place.
The 22-year old was eighth in the Spanish Open last month and admitted his first year on tour had exceeded all his expectations.
England's Lee Westwood who was two clear after four holes of the final round and seemingly in charge of the tournament collapsed on the back nine as dropped four shots from the 11th to the 14th and his 20th attempt to land this championship was doomed from there on in.
He finished on seven-under par after a 73 and in a tie for ninth place whilst the overnight leader Alejandro Canizares had a chance to get into the play-off if he eagled the last hole but his 25 foot putt was too high and he had to settle for a share of fourth spot with Miguel Angel Jimenez.
Jimenez finished with a flourish eagling the last and Ernie Els jumped up the board with a final round 67 to finish on eight-under level with Pepperell and South Africa's James Kingston
Els who saved his best for last said: "I actually started playing a little bit better yesterday late afternoon, but found something in my swing and my putting and so forth, so it was nice to finally start playing some decent golf."
Sergio Garcia who was at the centre of the racism row that overshadowed the build-up to the tournament could not get going and finished where he started on five-under par.
Final scores after the fourth round of the European PGA Championship at Wentworth on Sunday (GBR and IRL unless stated, par 72):
278 - Simon Khan 69-72-71-66, Matteo Manassero (ITA) 69-71-69-69, Marc Warren 69-70-70-69 (Manassero won play-off at fourth extra hole)
279 - Miguel Angel Jimenez (ESP) 76-69-67-67, Alejandro Canizares (ESP)
69-70-68-72
280 - Ernie Els (RSA) 72-69-72-67, James Kingston (RSA) 66-77-69-68, Eddie Pepperell 71-69-71-69
281 - Richie Ramsay 71-75-66-69, Francesco Molinari (ITA) 70-68-73-70, Lee Westwood 70-71-67-73
282 - Bernd Weisberger (AUT) 73-71-70-68, Gregory Bourdy (FRA) 71-73-70-68, Niclas Fasth (SWE) 70-71-72-69 Mikko Illonen (FIN) 67-76-70-69, Peter Uihlein (USA) 72-73-68-69, Pablo Larrazabal(ESP) 71-73-67-71, Shane Lowry 70-71-69-72
283 - David Drysdale 71-73-69-70, Gregory Havret (FRA) 70-71-71-71, Richard Bland 71-71-69-72, Sergio Garcia (ESP) 72-71-69-72, Edoardo Molinari (ITA) 72-71-68-72
284 - Fabrizio Zanotti (PAR) 71-75-70-68, Raphael Jacquelin (FRA) 71-71-73-69, Nicolas Colsaerts (BEL) 72-70-73-69, Branden Grace (RSA) 71-73-71-69, George Coetzee (RSA) 69-70-75-70, Phillip Price 73-69-70-72, Mark Foster 70-69-72-73
285 - Danny Willett 73-72-73-67, Darren Clarke 74-70-72-69, Alexander Noren (SWE) 74-71-71-69, Ross Fisher 72-73-68-72, Tommy Fleetwood 71-74-68-71, Alvaro Quiros (ESP) 70-73-69-73
286 - Anders Hansen (DEN) 70-74-73-69, Jamie Donaldson 71-75-73-67, Lee Slattery 71-71-69-75
Selected
287 - Thomas Bjorn (DEN) 69-74-75-69, Thongchai Jaidee (THA) 74-71-72-70
288 - Colin Montgomerie 71-75-72-70, Jaco Van Zyl (RSA) 75-69-73-71
289 - Martin Kaymer (GER) 70-74-73-72, Paul McGinley 71-75-70-73, Justin Rose 72-74-69-74
296 - Jose Maria Olazabal (ESP) 75-71-78-72