The Gunners signed the Armenia international in a swap deal that saw Alexis Sanchez complete a switch to Old Trafford.
Mkhitaryan failed to make an impact at Old Trafford during his 18-month spell at Manchester United following a £30m move from Dortmund.
The Arsenal number seven left his mark on the Gunner side in his first start following three assists in a 5-1 win against Everton last weekend.
The 28-year-old left the Bundesliga as the players’ player of the year, but Manchester United boss Jose Mourinho used Mkhitaryan sparingly.
While the Armenian midfielder won the Europa League and the League Cup last term, Mkhitaryan played a bit-part role under the Red Devils boss.
Former Spurs forward Crooks is backing Mkhitaryan to blossom into a top player at Arsenal.
“I liked Henrikh Mkhitaryan at Borussia Dortmund, I liked him at Manchester United and I adored what he did for Arsenal against Everton,” Crooks told BBC Sport.
“Mkhitaryan was used and abused at United but, under more of an ‘artistic director’, the Armenia captain looks as if going to be a big hit for the Gunners.”
Mkhitaryan scored in Manchester United’s 2-0 win against Dutch giants Ajax in the Europa League final in Stockholm back in May 2016.
The Gunners haven’t won the Premier League title since 2003-04 but Arsenal managed to get their hands on the FA Cup in three of the past four seasons.
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