The sole England cap looked set to be a mainstay in Sven Goran Eriksson's plans when he made his debut against Portugal at Villa Park in September last year but his form has been up and down since.
Dunn faces former side Blackburn Rovers for the first time on Saturday after Ewood Park boss Graeme Souness also questioned his form and whether he was focused purely on his game.
Blues boss Bruce, though, says Dunn will be aiming to get one over on his former employers and force his way into the England reckoning.
Bruce said: "The one thing 'Dunny' will want to do is play well against Blackburn. He is a Blackburn lad and was brought up through the ranks there.
"It is important he just goes and plays the game and he will handle the situation, no problem.
"He is a unique talent and we've got to get the best out of that talent.
"I think we've seen glimpses. He is a big player for us. He is eager to do well and please.
"England has got to be in his mind. He has the ability. He has got to aim to force his way into the squad for Portugal."
