"I know Robbie is going to be a very important player for us. Maybe he needs to score his first goal then he'll go on to score a lot more, as that's the type of player he is," said the Spaniard.
"When you arrive you want to score straightaway to relieve the pressure.
"He is just waiting and wanting to score that first goal and he is a great player to have in the dressing room.
"I know Robbie from watching him back when I was at Atletico, so if we want to win trophies we will need players like him."