FADING: Masters champion Hideki Matsuyama’s run at back-to-back majors ended with a 42 on the back nine and a 76.
SHOT OF THE DAY: Mickelson hit a long iron over a tree that just cleared a waste bunker and bounced onto the green on the par-5 second hole, setting up a two-putt birdie.
ROUND OF THE DAY: Patrick Cantlay had the only bogey-free round of the tournament but only made two birdies and shot 70.
NOTEWORTHY: At 50, Mickelson is the oldest 54-hole leader at a major championship since 59-year-old Tom Watson in the 2009 British Open at Turnberry. Watson lost to Stewart Cink in a playoff. The final group of Mickelson and Koepka has won a combined nine majors.
QUOTEWORTHY: “The hard thing when you get older is getting yourself in position where you feel a bit the butterflies and the nerves. We push too hard; we’ve got a bit of scar tissue, all that stuff, and it just doesn’t happen. But when you get there, the feelings come back you remember.” — Padraig Harrington.
KEY STATISTIC: Mickelson’s 209 was the same 54-hole score as Rory McIlroy in the 2012 PGA at Kiawah Island. McIlroy closed with a 66 and won by eight shots.