And Williams, who made substitute appearances in all five of Wales' RBS 6 Nations fixtures, is relishing the chance to prove what he can do in Phillips' absence.
"We've been given a huge opportunity to show how well we can perform in Japan," Williams told Wales Online. "With Mike [Phillips] away, me and Tavis [Knoyle] are going on tour looking for some serious game-time.
"It will be really competitive between us but whoever gets the nine jersey will be desperate to keep it.
"Robin [McBryde] has alluded a lot to the fact that there are 15 boys away with the Lions. So this is a massive opportunity for us to express ourselves and show what we can do - especially with places in the autumn squad up for grabs."