 McKenna reached the quarter finals of the inaugural Winmau World Masters in 1974.In 1989, he reached the final of the WDF World Cup, losing to Eric Bristow.It was at the 1990 BDO World Darts Championship where McKenna become notorious within the game, as the man on the receiving end of the first nine-dart finish at the World Championship, achieved by Paul Lim of the United States.