Masters champion Hideki Matsuyama slipped down the leaderboard with a three-round total of 1-over-par 217 at the PGA Championship on Saturday, eight shots behind leader Phil Mickelson.
Matsuyama briefly threatened for the lead by turning in 34 at the Ocean Course at Kiawah Island but struggled home in 42 to end the day with a disappointing 76 and dropped to a tie for 23rd after starting the day only two behind joint leaders Mickelson and Louis Oosthuizen.
Matsuyama, who is looking to win his second straight major after a strong performance at the Masters last month, had three birdies, five bogeys and a double bogey.
While the 29-year-old Japanese fell off the pace in the third round, Mickelson, a 44-time PGA Tour winner and five-time major champion, put himself on the threshold of another major milestone.
At 7-under-par for the tournament, Mickelson heads into the final round one ahead of fellow American Brooks Koepka, and two in front of South Africa's Oosthuizen, where he hopes to become the first man over 50 years old to win a major championship.
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