The 28-year old Scot, who got into a play-off in the recent Honda Classic, could count himself unlucky after hitting one of his best drives all week only for the ball to rest in a divot.
Just 125-yards out from the green and looking to get back under par in the championship, Knox put his second shot into a greenside bunker from where he walked off with a bogey in a round of 73 to finish tied 25th at one over par.
"It's been a tough four days and the course has been very tricky, one of the trickier courses on the Tour," said Knox who will now head to Orlando where he will be making his debut in the Arnold Palmer Invitational.
The veteran Australian John Senden, with two late birdies, took the title and with it an invitation to the Masters. Senden is noted for his stellar long game, but it was his short game that enabled him to secure victory as he pitched in from 70 feet at the 16th and then holed a 20-foot putt at the 17th to break clear.
He parred the last to card 70 and finish at seven-under-par 277, one stroke ahead of the American Kevin Na.
On the European Tour, Alejandro Canizares targeted further success after cruising to a wire-to-wire victory in the Hassan Trophy, his first Tour title since 2006.
Canizares took a six-shot lead into the final round at Golf du Palais Royal in Agadir, Morocco, and carded a closing 70 to finish 19 under, five clear of England's Andy Sullivan.
Sullivan charged through the field with a brilliant 63, the 26-year-old from Nuneaton covering the back nine in just 29, including birdies at the final four holes.
England's Seve Benson birdied the 18th to claim a share of third place with Sweden's Magnus A Carlsson, who had completed a 68 by holing from off the green on the last for par after a left-handed escape shot from the trees.
Canizares, whose previous victory came in the Russian Open on his third start as an affiliate member, would have won by a greater margin if not for a piece of bad luck on the 18th, where his approach rolled back off the green and up against a clump of turf from a divot that had not been replaced. The 31-year-old was told by a referee he was not allowed to move the turf and succeeded in moving the ball only a few yards with his third shot before it again rolled back down the slope almost to his feet.
From there he duffed his next pitch but at least allowed himself a wry smile before eventually getting up and down for a double-bogey 6. "It was a pity it ended like that, but who cares? I won the tournament so I am very happy," said Canizares.
"Hopefully this is the first step for a little bit of improvement in my career."
n England's Charley Hull claimed her first Ladies European Tour title, carding a stunning closing 62 before beating France's Gwladys Nocera in a play-off for the Lalla Meryem Cup. Hull, who will celebrate her 18th birthday on Thursday, holed from four feet for birdie on the first extra hole after coming from five strokes behind to tie with Nocera on 15 under par. The win capped a sensational 12 months for Hull, who started her professional career at the same event in Morocco last year and secured her first of five consecutive runners-up finishes.