"No, I didn't think he needed to (leave)," Johnson told the Sunderland Echo. "I know he was never prolific here, but I think he gives you so much.
"He works hard and he's got pace up front. He's difficult to play against, whether he's scoring goals or not.
"The way the Premier League is going now, everyone is lacking pace. He had that in abundance.
"I rated him highly."
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