The Sky Blues meet the revamped City in Ballarat in the Round of 32 of Football Federation Australia's inaugural cup competition and Arnold says it gives his side a good chance to learn how John van 't Schip's ex-Heart line-up performs.
City's marquee loan signing David Villa, formerly of Valencia and Barcelona, is not yet in Australia but Arnold is well aware that the Manchester City and New York City affiliate will be a dangerous opponent.
"It gives us a great opportunity to see what they've got before the first game of the A-League," Arnold said.
"David Villa is not here now but he's going to add a lot of strength to them in round one (on October 11).
"John van't Schip is a great coach and brings a lot of experience to Melbourne City.
"He knows the club inside out and with the extra financial clout no doubt they're going to be an even stronger team this year from last year and the years before.
"They're leading the way in spending money at the moment in the A-League and that brings its own pressure as well. They've got a lot of youngsters and handling the pressure will be new to them."
32-year old Villa, who is Spain's all-time leading goalscorer, signed with MLS expansion franchise New York City FC from Atletico Madrid in early June before being loaned to City until the end of 2014.
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