"You've got guys that only play T20 and that's their chance to play international cricket, so I think absolutely it's meaningful"
The narrow two-run margin was not enough to save an England side who had lost all their previous games in the competition
The unlucky Guptill also become international T20's highest run scorer after making 105 off 54 balls.
The hosts had set a target of 197, and restricted England to 184 for nine in reply.
"Our players have been in tremendous form coming off the Big Bash League and they are playing with freedom and they're playing fearless," says Warner
The win ensured Australia will play in the tri-series final in Auckland on February 21 with preliminary matches now switching to New Zealand.
Chapman and wicketkeeper Tom Siefert were included in the Black Caps' 13-man squad at the expense of Tom Bruce and Tom Blundell
Maxwell, who earlier took three wickets in two overs, was man of the match with an unbeaten 103 as the Australians chased down England's 155 for nine
Glenn Maxwell slammed a last-ball six to score a masterful century and lead Australia to a five-wicket victory over England
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