By STEPHEN HAWKINS
AP Sports Writer
McKINNEY, Texas (AP) — Sebastian Munoz shot a 12-under 60 in the opening round of the Byron Nelson. He is the first PGA Tour player ever with two rounds of 60 in the same season. Munoz was at 2-under par Thursday after taking a penalty shot because of a wayward tee shot at the eighth hole. The 29-year-old Colombian then was 6 under over his next four holes with two eagles. He also had a 60 in the opening round of the RSM Classic at Seaside in Georgia in November. He has a four-stroke lead over a group that includes defending Nelson champ K.H. Lee.