"You can see in training, and in our pre-season games, that he's looking sharper. He's looking more determined, tracking back to help the full-backs,"
"He's definitely working harder and trying to impress. He's a brilliant player."
He is also pleased to be starting from a more central role.
"A lot of time I get told not to track back and to conserve my energy, stay upfield and save myself for when we are attacking," he said. "Berbatov is certainly better when he's full of energy and getting touches of the ball."