He is expected to return at Wigan on Saturday after being rested for the FA Cup win over Blackburn last weekend, and Petrov feels the England player has plenty of other qualities which make him worth his place even when his finishing power temporarily deserts him.
The Bulgaria international said: "Gabby has been in fine form with his goals this season and there's been some really important ones he's scored already.
"Just look at his goals against Birmingham City, a late, late winner, and the decider against Manchester United which gave Villa their first win there for a long time.
"He even had a spell where he scored five goals in five games, which was a fantastic tally so early on in the season.
"But, even when Gabby doesn't manage to get his name on the scoresheet, his contribution is still massive.
"He keeps taking on opposition players and holding the ball up well. He is a great outlet for us.
"It's great to see someone develop like that - and it's true a lot of people forget how young he still is too.
"Despite his age, he's a vital asset to the team."
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