 Wimalashantha made his cricketing debut during the 2005 Under-23 Tournament, in which he played four matches.Wimalashantha made a single List A appearance, during the 2005-06 season, against Sebastianites Cricket and Athletic Club, and though he did not bat in the match, he bowled 6 overs, conceding 37 runs.Wimalashantha made a single first-class appearance for the side, during the 2005-06 season, against Nondescripts Cricket Club, scoring a single run in the only innings in which he batted.