Seamus Power is six shots off the lead ahead of the final round at the John Deere Classic.
The Co Waterford native carded a 68 on Saturday which lifted him up to 10 under and keeps him in touch with the top 20 at the TPC Deere Run course in Illinois.
Munoz, the first round leader after birdying his last five holes on Thursday for an eight-under 63, had a mixed front nine of three birdies and two bogeys on Saturday, before three more birdies in an unblemished back nine.
At 16-under he led by a stroke from American Brandon Hagy, who mixed five birdies with a bogey in his 67.
Five more Americans were a further shot back at 14-under including Scott Brown, who took the day's best round with a 63 including five birdies in six holes from the 10th to the 15th.
One more stroke back was a group of four players including overnight leader Luke List, who followed Friday’s 63 with an even 71.
Power made a fast start, with a trio of birdies in a row across the first three holes.
Another on six maintained his momentum before a bogey on nine.
Further bogeys on 10 and 11 saw him slip back but he rallied with two birdies in a succession on the 16th and 17th to finish round three in a tie for 22nd.