An opening-round 66 in Abu Dhabi was a positive sign, but he followed with a second-round 75 and eventually finished tied for 34th. Two weeks later he teed it up in the Euro Tour’s Saudi International, tying for 17th and continuing to show signs of progress. Still, there was a bit of mystery on just how good his left knee felt.

As he struck perfect shot after perfect shot on a board-of-tourism day at Riviera, as he charmed his pro-am partners, and as he mused on digital minimalism and ADHD and global warming in his Genesis Invitational press conference, Rory McIlroy displayed the quiet confidence of man at the top of his profession, in the prime of his life.