The first round of golf's only major championship of the 2019-20 season wrapped up Thursday evening at TPC Harding Park in San Francisco, leaving us with a diverse leaderboard and a load of action to dissect at the 2020 PGA Championship. Bryson DeChambeau broke his driver and subsequently cruised into contention by crushing the field in driving distance, Tiger Woods worked his way to within a few strokes of the lead, and three of the world's top-five ranked golfers -- including world No. 1 Justin Thomas -- finished the first 18 holes of the tournament above par.
Through one round, it's Jason Day and Brendon Todd who stand together as co-leaders at 5 under with Day firing a bogey-free 65 and Todd getting there with a bogey-free final nine. Behind the two are a slew of other contenders at 4 under, among them back-to-back PGA Championship winner Brooks Koepka, Xander Schauffele, Martin Kaymer and Brendan Steele.
CBS Sports has broken down the PGA Championship leaderboard with all the notable action from Round 1 below, starting with Day and Todd.
T1. Jason Day (-5): In masterfully maneuvering the course Thursday, Day made his bogey-free 65 look effortless. He drove it well off the tee, commanded his irons with confidence and found some success on the greens, too. Said Day after the round: "Yeah, pretty sound the whole way around." It was his first bogey-free round at a major championship since the third round of the 2017 Open Championship. This after Day led all golfers in bogey-free major rounds from 2010-16, per Elias Sports Bureau.
Want the sharpest DFS advice, picks and data-driven golf analysis? Listen below and subscribe to The First Cut Golf podcast where we explain what's happening on the course so you can win off of it.
T1. Brendon Todd (-5): While Todd's 65 wasn't as tidy as that of Day -- he carded two bogeys on his opening nine -- he managed to string together a 3-under-par, bogey-free final nine to get him into the tie atop the leaderboard. Todd was far from the favorite entering this event, but the 35-year-old has twice won on tour this season -- at the Bermuda Championship and at the Mayakoba Golf Classic. He also worked his way into contention last week in Memphis before fading down the stretch. Todd's not a long and powerful golfer, but he's a wizard with the putter, which kept him in the mix Thursday by gaining 3.161 strokes on the field putting.
T3. Brooks Koepka, Scottie Scheffler, Martin Kaymer, Xander Schauffele, Bud Cauley, Zach Johnson, Justin Rose, Brendan Steele, Mike Lorenzo-Vera (-4): Coming off a T2 finish at the WGC-FedEx St. Jude Invitational last week, Koepka -- the back-to-back PGA Championship winner -- picked up where his flamethrowing left off in Memphis. He crushed off the tees Thursday and showed good patience and control with his irons, finishing his round with six birdies and using his length to his advantage. Koepka is peaking at the right time after a rollercoaster 2020 that has seen him deal with lingering injury concerns, and he's striking it well enough to be a legitimate three-peat threat at this event.
T12. Tony Finau, Daniel Berger, Gary Woodland and five others (-3): Despite really struggling to find a groove on the greens -- and despite hitting only five 14 fairways -- Finau turned in a nice 3-under 67 Thursday, using his brilliant iron game to bridge the gap of inconsistencies between the tee and green. He could just as easily be leading the field if not for some fairly makeable misses on the greens and some struggles controlling the driver. He's in a really good position in spite of all that and figures to be one to watch Friday if he can line out some of those troubles.
T20. Tiger Woods, Bryson DeChambeau, Adam Scott, Patrick Reed and nine others (-2): No one made an under-par score look more laborious than Woods did in Round 1. And it wasn't because of his back. He continuously got himself in trouble off the tee by driving with distance but with little control, yet Tiger continuously bailed himself out in spectacular fashion with his approach and his putter. Woods recorded 1.228 strokes gained in putting on the field after switching putters for this week, and while saving himself from his driver doesn't seem sustainable, he finished strong and had some good moments that could portend well for his contention into the weekend.
As for DeChambeau, the most memeable golfer on tour had the most viral moment of Thursday with him leaning on his driver, causing the club head to separate from the shaft. He was 4 under through 10 holes but faded down the stretch, playing his final eight holes at 2 over. Nevertheless, the big bomber remains well in it entering Friday's second round
T33. Dustin Johnson among 14 others (-1) -- Consecutive 80s at the Memorial Tournament followed by a WD at the 3M Open raised concern for Johnson, whose back has been giving him fits. But he picked up where he left off last week at the St. Jude Invitational, where he finished T12 with an opening-round 69. He struggled with the putter but boomed his drives on average 311.5 yards, trailing DeChambeau only by a few yards. He looked confident and relaxed, despite playing his final three holes at 2 over.
T49. Rory McIlroy, Jon Rahm, Tommy Fleetwood, Bubba Watson, Hideki Matsuyama among 14 others (E): McIlroy birdied his first hole of the day going off No. 10 then quickly dug himself into a trench, carding bogeys on 12, 13 and 14 before recovering with birdies on 16 and 18. That was the theme of his day in his final nine as he was missing fairways and leaving himself with 4- and 5-foot putts that proved to be his Achilles heel throughout the afternoon. Rahm played a similar round at even-par but settled in down the stretch. I was impressed with his poise to finish at 2 under on the back nine after struggling out of the gate with bogeys on 2, 6 and 9.
CBS Sports was with you the entire way updating this story with analysis and highlights from Round 1 of the PGA Championship. Keep on scrolling for more from the first 18 holes at TPC Harding Park, and click here for a more detailed leaderboard.