Forced out of action due to the drug scandals that have rocked his cricket career, embattled Pakistan pacer Mohammad Asif says he is desperate to prove his worth on the field to get over the gloom.Asif last played cricket when he figured in the inaugural Indian Premier League but is out of action since then as he is battling to get his name cleared in a dope scandal after testing positive for a banned substance in the same tournament.I am very disappointed but I will definitely make a comeback