Watson was not extended to overcome Kisner, who appeared to have left all of his good golf behind him in earlier matches including the morning semi-final where he defeated a determined Alex Noren at the 19th hole.
Watson made it to the afternoon final match-up by defeating Justin Thomas in their semi-final 2&1.
The two-time Masters winner must now be looking ahead to the first week of April with a real belief he can win a third, the momentum from his recent run of form likely to carry him on to great things at Augusta National.
For Watson it was his second victory of 2018 following his win at the Farmers Insurance event at Riviera Country Club, his second WGC title and his 11th PGA Tour title, the 39 year old now moving back inside the world top twenty-five after being outside the top 100 prior to his Riviera victory.
A significant improvement in putting has been the key to much of that progress, additional loft added to his putter by Ping seemingly making a big difference on the greens.
Watson was to be leaving Sunday morning for an overseas vacation with his family, not expecting to make it as far as he did in the event, but that he earned close to US1.8 million for delaying that time away might just ease any concerns in that regard.
Watson had only once previously, in seven attempts, made it past the Round of 16 in this event but there have been genuine signs in 2018 that his game is returning to the level it was when reaching as high as number 3 in the world.
In the match for 3rd and 4th place Alex Noren was never behind in his encounter with Thomas eventually winning 5&3.
Cameron Smith did best of the Australians when he made it to the quarter finals before being beaten by Alex Noren.
DAVID NORTHEY - RECOVERY SHOT SELECTION
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