Clarke's 30-foot birdie putt on 18 seals first European Tour win since '03
Clarke, needing a birdie to avoid a playoff with playing partner Derksen, and having nearly putted himself out of the tournament on the 16th and 17th holes, found the middle of the cup to card a 1-over 73.
A thrilled Clarke, who lost his wife Heather after a long battle with cancer two years ago, said: "It was always going to be a difficult hurdle for me to get back into the winner's enclosure after Heather passed away.
"But to turn around and make a brilliant last and win the cup feels pretty good," Clarke, whose last win on the European Tour was at the WGC-NEC International in Ohio in 2003, said at the Tomson Shanghai Pudong Golf Club.
Clarke, leading Derksen by two with three holes to play, did all he could to throw the tournament away, missing a short par putt on the par-4 16th, then bogeying the par-4 17th to fall back into a tie for first place.
"My mind started going forward probably about 14 onwards. I lost my concentration and started thinking about Heather and the boys [sons Tyrone and Conor] and bits and pieces," Clarke said.
Few would have expected Clarke to make his putt after Derksen ratcheted up the pressure by placing a recovery chip from behind the green to within two feet of the flag.
But the putt dropped where so many shorter ones had missed, leaving the Ulsterman with his arms raised in the air.
"This is the very top. I have been working harder than I have ever worked on all aspects of my game, putting in nine, 10, 11 hours a day and it is nice to see it pay off," said Clarke, who picked up $379,700 in prize money.
Derksen, who conceded a two-stroke lead to Clarke after chipping into the water for a double-bogey on the 14th, battled manfully to get back into contention, sinking long putts to save par as Clarke wilted on the greens.
World No. 13 Henrik Stenson of Sweden finished fourth a stroke behind at 4-under after carding a final round 68.
Two-time U.S. Open champion Retief Goosen finished tied for seventh after shooting 73 on Sunday.
Clarke, who helped Europe to an emotional victory at the 2006 Ryder Cup in Ireland weeks after his wife's death, said the win had re-set his sights on claiming a spot in the team again in September.
"If I qualify for the Ryder Cup team, fantastic. That is back within realistic goals now," he said.
MORE GOLF HEADLINES
- Tiger's long-awaited 1st course design opens
- McIlroy again is European Tour golfer of year
- Fritsch's 66 takes Web.com Tour Q-School
- Inverness Club to host 2019 U.S. Junior Am