Scottie Scheffler came into the CJ Cup Byron Nelson as the overwhelming favorite to win the title and is not leaving much room for doubt. After the first 36 holes, the World No. 1 leads by six shots and is on his way to his first victory in 2025.As if to dispel any speculation that his dominance was due to a weak field, Scheffler wasn't content to simply lead at will. His 36-hole score of 18-under 124 is a new record for the event and one of the best scores in PGA Tour history.Scheffler got off to a flying start on Thursday, carding a 10-under 61 with an eagle and eight birdies (no bogeys). The score was just one stroke off the TPC Craig Ranch course record of 60 set by Keegan Bradley in 2013.Scheffler was no less sharp on Friday, shooting another bogey-free round of 8-under 63 with an eagle and six birdies. Not even a six-hour weather delay distracted him from his tournament focus.He and Sam Stevens, who sits in second place, are the only players in the tournament without a bogey.The two-time Masters champion's 124 is also the best 36-hole score of his PGA Tour career. In fact, it is tied with three other players for the second-best 36-hole score in Tour history: Pat Perez at the 2009 American Express, David Toms at the 2011 Colonial and Jason Day at the 2015 BMW Championship.Justin Thomas holds the PGA Tour's lowest 36-hole score (123) at the 2017 Sony Open in Hawaii."We're on a golf course where you've got to make some birdies, and the conditions today were changing a good amount," Scheffler said after his second round."Obviously with the huge rain delay, that was a challenge as well. Getting back out and playing in some wind and some pretty wet fairways, but overall, it's great to be playing at home. This tournament means a lot to me, and it's nice to be playing good golf as well."This is Scheffler's sixth start at the Byron Nelson. He has consistently made the cut at TPC Craig Ranch, with a T5 in 2023 as his best finish.This event holds special significance for him as it marked his PGA Tour debut. It came in 2014, when a 17-year-old Scheffler received a sponsor's exemption just months after winning the US Junior Amateur.The Ridgewood, New Jersey, native and Dallas resident made an impressive debut, finishing in a tie for 22nd place in that edition of the event with a final score of 4-under.More Golf: Rory McIlroy Teaches Jimmy Fallon a Lesson on Tonight Show