England claimed a stunning victory over Australia in the first Twenty20 international in Southampton as the tourists' batting order collapsed to fall two runs short. (More Cricket News)
Australia - the world's top-ranked T20 side - were playing for the first time since March due to the coronavirus pandemic but initially showed few signs of rustiness.
They were coasting towards an opening win with a strong response to England's 162-7, a total boosted brilliantly by Dawid Malan's 66.
However, a flurry of sloppy wickets left Australia needing 15 runs from the final over and Tom Curran held his nerve to deny Marcus Stoinis (23 not out).
Defeat was tough on Finch (46) and opening partner David Warner (58), who had the Aussies 98-0 in the 11th over before the skipper found Chris Jordan at mid-off, with Jofra Archer (2-33) the beneficiary.
Steve Smith (18) kept the scoreboard ticking over, but he and Glenn Maxwell departed to Adil Rashid (2-29) in the same over as Australia started to stutter.
Although Warner chopped on, England still faced an uphill battle until a sublime penultimate over from Jordan, who gave up just four runs and ran out Ashton Agar with a direct hit.
Curran took on Stoinis and came out on top despite a big six off the second ball, clinching an unlikely England triumph.
The hosts' own innings had been similarly topsy-turvy as Australia paid early for the decision to send their opponents in to bat when Jos Buttler (44) plundered 16 runs off Agar (2-32) in just the second over.
But an initially dominant England innings turned at the hand of Agar as he returned to the attack and atoned for his dismal start with two big wickets.
Buttler went first - straight to Pat Cummins at deep midwicket - before the in-form Tom Banton followed as Finch took a stunning running catch over his shoulder.
Australia's fielders continued to capitalise on the good work of their bowlers as Eoin Morgan and Moeen Ali were each then caught off Maxwell (2-14), England struggling from 64-1 to 108-5.
Morgan's men needed a hero and found one in Malan, whose knock off 43 balls - including five fours and three sixes - provided the platform for a fine win.
Malan was named man of the match and his record in the shortest format is one of remarkable consistency, with this his eighth score above 50 in 14 innings.