The Senior PGA Championship, established in 1937, is the oldest of the five major championships in men's senior golf. It is administered by the Professional Golfers' Association of America and is recognized as a major championship by both PGA Tour Champions and the European Senior Tour. From Wikipedia
The former Masters champion overcame a two-shot deficit to defeat Padraig Harrington at Congressional, marking a remarkable resurgence in his golfing career after serving a prison sentence.