Doyle has struggled for goals this season but he has netted in the club's last two Championship games, and Saunders believes that he looks a "different player" to the one that he saw when he arrived at Molineux in January.
The 48-year-old told the Birmingham Mail: "I'm pleased Kevin's playing well - he's playing like Kevin! He's scored twice and he's shown a bit of sharpness and pace to win us the penalty on Monday - he's run away from their defenders and for me, the goalkeeper should have been sent off.
"I'd like to think that making him captain has helped, but you can't keep good players down for long.
"He's been down and now he's dragged himself out of it. He got a goal and now he looks a different player - he looks a yard sharper."
The Republic of Ireland international is expected to lead his side's attack when they play Bolton Wanderers on Saturday.