The 1978 PGA Championship was the 60th PGA Championship, played August 3–6 at Oakmont Country Club in Oakmont, Pennsylvania, a suburb northeast of Pittsburgh. John Mahaffey won his only major championship in a sudden-death playoff over Jerry Pate and Tom Watson. PGA Championship 1978: August 3–6, 1978 at Oakmont Country Club. Champion: John Mahaffey, at 276 (−8), playoff. Wiki link