Arsenal manager Arsene Wenger believes that Nicklas Bendtner proved that he had what it takes to become a top striker during his loan spell at Birmingham.
The Gunners travel to St Andrews this weekend as they continue their Premier League title challenge against Alex McLeish's men.
If Bendtner recovers from an ankle problem to lead Arsenal's attack in the Second City, it will mean the Dane returns to a ground where he spent time on loan in 2006/07.
Wenger was always confident the 22-year-old would develop into an offensive threat and thinks he benefited greatly during his time with Birmingham.
"I saw Nicklas Bendtner in the reserves and he had an impact in the games," the Arsenal manager recalled. "But you felt as well that he needed to go somewhere to toughen up.
"There is no better place in the world than the Championship to give a player a realistic view of how hard this job is.
"He went there and in fairness to him, he became a regular player straight away - that shows you he has the qualities to survive at the top level."
Bendtner had a nightmare outing in the recent match against Burnley, but responded with a hat-trick against Porto in the UEFA Champions League and a crucial winner against Hull City.
Wenger is therefore not alone in having been suitably impressed, with the youngster also earning praise from team-mate Andrey Arshavin.
"Nick creates more space for the players behind him, and that offers us more time and possibilities to do something special," said the Russian.
"He is good in the air, he wins a lot of balls that way and through this we can gain even more possession. We can play differently with him in the side."
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