'It's something you wonder if you'll ever get to, to win, and it's a great feeling,' said Lonard.
Lonard opened the tournament with a 62 at Harbour Town but lost the lead after a shaky second round. He battled back to secure a one-shot lead over Clarke with one round to play but soon found himself trailing his playing partner by four strokes on the front nine.
Clarke ran off three consecutive birdies from the first to jump to 13 under while Lonard bogeyed each of his first two holes. Clarke drained a 5-foot putt for a birdie at the fifth but Lonard managed to keep pace with a birdie of his own at the very same hole.
At the par-4 sixth, Clarke hit his tee shot into a bunker and hit out to 8 feet. He missed the par putt and dropped another shot at the par-3 seventh. Lonard then hit his tee shot to 20 feet and converted the birdie try at the seventh to move within one of Clarke at 11 under.
'I got off to a great start, thought everything was going well, and just started making some bad swings, and it went from bad to worse, and I seemed to be fighting that hook all day,' said Clarke.
Clarke's problems continued at the par-4 eighth where he hit his drive into the water en route to a double bogey and just like that Lonard was back in the lead. Lonard wasn't out of the woods, however, and dropped a shot at the ninth to join Clarke in a tie atop the leaderboard.
'I hung around the mark, and he made a couple mistakes, which isn't that hard to do here,' said Lonard. 'The birdies were hard to come by, the wind was a bit fluky, the greens were really tricky, so I was trying to hit greens in regulation and give myself a lot of opportunities.'
Clarke played his approach to 16 feet for a birdie at the par-4 12th to take a two-shot lead while Lonard bogeyed the hole. Clarke made a mess of the par-4 13th, however, for another double bogey and the wheels kept coming off as the 36-year-old bogeyed each of his next two holes two fall back to 7 under.
Lonard was having problems of his own down the stretch with bogeys at the 14th and 17th, but he was able to hang on to a piece of the lead with one hole to play.
Lonard hit a solid drive at the last and knocked his second shot to 18 feet. Clarke then gave the tournament away when his approach to the 18th missed badly to the left and found the thatch. Clarke took a drop and walked away with another double bogey while Lonard was left to celebrate his first win on the U.S. circuit.
Love, a five-time winner of this event, tallied three birdies and three bogeys for a round of 71. Furyk posted a 69 on Sunday while Andrade birdied the par-4 18th for a 68 and his share of second.
'I got off to a bad start,' said Love. 'That kind of killed me, and then I was fighting the whole rest of the way.'
Stephen Ames, Rod Pampling and Thomas Levet tied for sixth place at 4-under-par 280. Nick O'Hern was one shot further back at 3-under-par 281 after a round of 69.
Scott Verplank, Matt Kuchar and Michael Allen followed at 2-under-par 282.