DiMarco takes a three-shot lead over three others into the final round of the inaugural SEI Pennsylvania Classic at the Waynesborough Country Club in Paoli, Penn.
Saturday, DiMarco fired a 5-under-par 66 to move to 12-under-par through 54 holes, three strokes clear of Loren Roberts, Frank Lickliter and fellow Gator Mark Calcavecchia.
DiMarco began the third round one shot back of Lickliter and Calcavecchia. After a front-nine 2-under-par 33, DiMarco gained his first share of the lead by dropping an eight-foot birdie putt on the par-4 11th.
After two consecutive pars on the 12th and 13th, DiMarco stuck another tee shot to within ten feet at the par-3 14th. The ensuing birdie gave DiMarco the solo lead at 11-under, one shot lower than Lickliter.
Playing in the final group with Calc, Lickliter fell two off the pace by bogeying the 14th, when his tee shot flew the green. It was Lickliter's first bogey of the tournament. But the 31-year-old atoned for his iron mistake by sinking a 30-foot birdie putt at the par-5 15th.
However, as was the case at the par-3 14th, the par-3 17th proved to be a two-shot hole. DiMarco drained a 15-foot birdie putt to move to 12-under, while Lickliter missed a four-footer for par to fall to 9-under.
The two would remain in their respective positions, as each man parred the home hole.
'I've never (had a final-round lead) here on Tour,' said DiMarco. 'Up around it. I've been one back or even, but I've never had a two- or three-shot lead.
'I like it right now. Spot me three tomorrow, I like that.'
DiMarco will be paired with Roberts on Sunday. Roberts tied DiMarco's third-round 66 to earn a spot in the final group.
'I'm just going to go out and start out with the idea that if I can go through the first five holes and be, you know, 1-under for the round, I've got a real shot; I'm right there.'
Lickliter and Calcavecchia each carded rounds of 1-under-par 70 on Saturday. Once again, the two men will be paired together over the final 18 holes.
'I've still got a shot,' said Calcavecchia after birdying the par-5 18th. 'Chris has never won before. I'm sure he'll be a little nervous.
'You know, I've just got to hope things go a little bit better tomorrow. Nothing really good happened to me today. And as you know without a little luck in this game, you can forget it.'