Rookie Jake Knapp closing in on maiden PGA Tour title at Mexico Open

Knapp had seven birdies as he carded a 63 to move to 19-under-par at Vidanta, four clear of fellow PGA Tour newcomer Sami Valimaki of Finland.

The American opened with a pair of birdies and added five more in six holes to reach the turn in 28.

"I can't complain obviously. Feel like I struck the ball about the same as the last couple days. Just hitting it really well, driving it well," Knapp told pgatour.com.

"Was able to roll in some more putts. Felt like once I was able to see a couple go in early, it just felt like kind of everything was going in for a little while there."

Matt Wallace had started the day alongside Knapp in a four-way tie for the lead, but the Englishman could only manage a level par 71 to finish the day eight strokes off the pace.

He was joined at 11-under par by Scotland's Robert MacIntrye, who shot a 65 with four birdies topped off by an eagle at the 18th.

Canada's Ben Silverman, Sweden's Henrik Norlander and Chan Kim were on 12-under-par, completing a top five without a win on the PGA Tour.

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