Brooks Koepka held off world number one Dustin Johnson to retain his US PGA Championship title and win a fourth major on a dramatic day at Bethpage.

The 2017 and 2018 US Open champion, who had a seven-shot lead at the start of the final round, saw that cut to one after four bogeys from the 11th.

But Johnson dropped shots on the 16th and 17th as Koepka, who carded a four-over 74, won by two on eight under.

England’s Matt Wallace tied for third, earning his best finish at a major.