MIAMI (AFP) - Jason Day sank a 12-foot birdie putt at 17 and rescued par from a bunker at 18 Sunday to win the PGA Arnold Palmer Invitational by a single stroke.

The 28-year-old Australian became the first wire-to-wire winner at Orlando's famed Bay Hill layout since Fred Couples in 1992, just weeks before Couples went on to win the Masters.

Day, who rises to world number two with the triumph, hopes to fit himself for a green jacket at the year's first major tournament in three weeks after collecting the trophy from Palmer, an Augusta National legend.