But pull off a miracle she did.
With South Australia needing four runs for victory with five wickets in hand at Hobart's Blundstone Arena on Saturday night, Coyte took three scalps and effected a reflex run out at the non-striker's end.
The visitors needed three to win off the final ball, but managed just a single as Tasmania secured back-to-back titles with a one-run victory.
"It's probably one of the best games of cricket I've ever watched," Coleman, who took up the role in November, said.
"You just never know when Coytey has got the ball. But to be honest I thought it was a long shot. One per cent probably.
"I've seen Coytey do ridiculous things so many times. I thought this one was a little bit out of her reach, but she proved me wrong.
"It'll be played everywhere. I can't wait to go back and watch it."Â
In all, South Australia lost 5-1 in the final over with a run out on the last ball, leaving them runners-up for the second year in a row.
Tasmania's Emma Thompson, who will retire after more than a decade with the team, didn't play in the final but watched from the edge of her seat on the sidelines.
"Exciting, sickening, everything. It had the full gamut of emotions. I need to go back and rewatch it to believe it actually happened," she said.
Thompson made her first underage state appearance with Coyte, who became the first player to win WNCL titles at three different clubs, in the NSW under-17s.
"She's been an amazing friend for a long time. I said ... on the sidelines as she was about to start the last over 'if anyone can do this, I know Coytey can'," Thompson said.
"She's performed in pressure situations at every single level. (I) had a lot of hope that she could do it."
In a chase punctuated by rain delays, South Australia needed 23 runs to win off the last 18 balls under an adjusted Duckworth-Lewis-Stern target.
Tasmania had earlier posted 264 on the back of 110 from skipper Elyse Villani, who also hit a century in last season's final.