The Portuguese has retuned to his best form recently, scoring three times in his last two appearances.
"[Bernardo] is on fire at the minute," Sterling said. "The last goal there speaks for itself.
"He has been in incredible form and long may it continue. If you look around in our team there are a few players in each position. Every player starts for their national team.
"The manager has got loads of players at his disposal and it is a great thing to have in a team."