Hadlee was a right-arm pace bowler. Initially extremely quick, as the years progressed he gained accuracy, movement off the wicket and in the air, and a reputation that probably gained him quite a few wickets on its own. His economical action was notable for his close approach to the wicket at the bowler's end (to the point where he occasionally knocked the bails off in his approach), a line which meant he was able to trap many batsmen leg before wicket.
His middle-order batting was usually aggressive and enterprising, and, oddly enough, left-handed.
Hadlee was, unusually, knighted for services to cricket before his playing career had finished. He is currently the chairman of the New Zealand board of selectors.