Van Pelt began the day four behind overnight leader Emiliano Grillo, but four birdies on the back nine gave him a five under par round has put him into the lead.
It was an effort matched by compatriot Jason Dufner who is second on 11 under, with four bogeys on the back nine ensuring Grillo is a further shot back on 10 under.
Van pelt made the perfect start when he putted from 10-feet for a birdie on the first, but dropped one at the sixth following a poor bunker shot.
More excellent putting at seven and 11 brought him back into the mix, before a chip on 15th and his monster putt on the last put him in front.
"Once in a while a hole just gets in the way," Van Pelt told the European Tour website. "I felt like I hit a pretty good second shot, just carried about five yards further. I was just trying to get the ball down there and two-putt and get out of there, and lo and behold, it goes in the hole.
"There's still a lot of golf to be played. It was just nice to finish with a birdie like that and hopefully take that into tomorrow.
"Jason is a great player, Grillo is playing well and he's probably going to come out and probably shoot a low one tomorrow. You've got to drive the ball straight and then put the ball in position on the greens, because they have a lot of slope and they are getting firm and they are getting fast."
Dufner was equally pleased with his round and hopeful of picking up the win.
"It was a nice day to get a good score and move up and have a realistic chance of not having to do anything crazy tomorrow and being in contention to try to win the tournament," he said.
"Sometimes in the middle of a round, something happens that spurs you to some better play, and I got a little bit of a tough break on seven on my tee ball. Thought it would be in the fairway but hung up in the rough, which put me a good way back and I ended up getting into a bunker 70 yards or so and hit it over the back and then chipped in. "