The son of former Zimbabwe batsman Andy Waller, Malcolm is a middle-order batsman and offspinner who is trying to forge a cricketing career of his own. He first represented Zimbabwe at Under-15 level in 2000 before re-surfacing for Mashonaland in the Faithwear one-day competition in 2004. His appearances were sporadic until he finally established himself in 2007-08, though his performances - apart from in Twenty20 cricket - were fairly ordinary. But good club form with Harare Sports Club in the Vigne Cup helped win him selection for the Bangladesh tour in 2008-09. His most notable performance for Zimbabwe to date is an aggressive 63 in the thumping win over Kenya in 2008-09 - a series that Zimbabwe dominated from start to finish. His cousin, Nathan Waller, has represented Zimbabwe Under-19.