Brooks Koepka remains in contention to complete a US PGA Championship three-peat after keeping new leader Dustin Johnson in his sights on Saturday.

Johnson will take a one-stroke advantage into the final round after firing a crisp 65 to reach nine under, but the 2019 runner-up looks set to face a strong challenge from the man who beat him to last year's title.

Back-to-back champion Koepka (69) picked up two shots over the final three holes to recover from a potentially damaging run of three straight bogeys.

Overnight leader Li Haotong coped less successfully with the pressure, carding a costly three-over 73 that included three bogeys and a double at the 13th.

8 birdies. #PGAChamp leader. @DJohnsonPGA pic.twitter.com/0nZUwaZEiK
— PGA Championship (@PGAChampionship) August 9, 2020

Johnson, four shots back through 36 holes, ran into trouble with a double bogey of his own at the ninth, before steadying to finish with eight birdies on moving day.

The one-time major champion holds a narrow lead over Scottie Scheffler (65) and Cameron Champ (67), who are tied for second.

Cole Morikawa (65) and Paul Casey (68) are level with Koepka at seven under, but all eyes will be on the 30-year-old American on Sunday.

He could become the first golfer to win the tournament three times in a row since Walter Hagen in the 1920s.

Six men, including the improving Bryson DeChambeau (66) and 2015 winner Jason Day (70), are a further shot back at six under.

Tiger Woods fell well out of contention after carding a two-over 72 for the second successive round.