Dual grand slam finalist Mark Philippoussis says Alex de Minaur needs to "get outside his comfort zone" if he wants to finally knock off big dogs Carlos Alcaraz and Jannik Sinner.
Facing Alcaraz in the Australian Open quarter-finals on Tuesday, De Minaur will need to end a 0-5 run of career losses against the world No.1 Spaniard while he's winless in 13 matches against two-time Melbourne Park champion Sinner.
