"Tom is one of the best competitors of all time. He's going to bring that fire and unwillingness to lose and mental strength that has defined his career."
At the 2009 British Open, Watson missed a par putt on the 72nd hole at Turnberry that would have made him the oldest major champion in the history of the sport.
The American has a warm relationship with Scotland, the country where he won his first major title at Carnoustie in 1975 and where he would eventually win half his major crowns.
His appointment was announced by the USPGA on nationwide television, with predecessor Love having relinquished his post after what was dubbed the "Meltdown in Medinah" in the U.S. but the "Miracle of Medinah" in Europe.
"We've got the right guy," rallied USPGA president Ted Bishop.