While scores are typically low at the Deutsche Bank Championship, the course proved a stern test during Friday's opening round. Here's how things look at TPC Boston, where Brendon de Jonge set the early pace and leads by two:
What it means: Birdies were hard to come by in the early going, as Day's opening 68 was among the best totals before the afternoon wave hit the course. De Jonge later grabbed the top spot and increased his lead to two with a closing birdie, moving the Zimbabwean one step closer to what would be his first PGA Tour win after 27 prior top-10 finishes.
Round of the day: De Jonge opened with a birdie and added two more circles en route to an outward 32, then added birdies on Nos. 1 and 2 to reach 5 under. While he bogeyed the next hole, he countered with birdies on Nos. 5 and 9 to post the day's low total despite hitting only 11 of 18 greens in regulation.
Best of the rest: A winner here two years ago and a runner-up last week in New Jersey, Stenson is again in the mix after an opening 67. Stenson made eight birdies, including two over his final three holes, as the former FedEx Cup champ is once again raising his game during the postseason.
Biggest disappointment: Perhaps it wasn't the irons. After an unexpected missed cut at The Barclays with new equipment, Jordan Spieth switched back to his old sticks but still stumbled to a 4-over 75 in the opening round. Spieth's tumultuous round included more bogeys (eight) than pars (six), and he now has work to do simply to make it past the 36-hole cut.
Main storyline heading into Saturday: The hottest player in the field is still the player to watch. Day birdied his first three holes en route to a 68, and while he trails de Jonge by three shots he clearly has not lost any momentum since his six-shot romp at Plainfield. With Spieth and Rory McIlroy (70) off to somewhat slow starts, the No. 1 ranking is still in the Aussie's sights.
Shot of the day: Is a par 4 considered "driveable" if you find the target with an iron? Dustin Johnson put that theory to the test on the 289-yard fourth hole, finding the putting surface with a 4-iron off the tee that set up an easy birdie.
Quote of the day: "I felt tee to green, the way I drove the ball, hit my irons, for the most part it was very good." - McIlroy