Her 61 off 41 balls against India set Australia up for a narrow nine-run victory last August before Ashleigh Gardner turned the screw with two wickets in as many balls and three for the match. On Saturday night, opener Mooney expertly marshalled Australia's pursuit of 154 with an identical score - this time unbeaten and off 47 balls - in another tight finish as wickets fell around her, all the while exuding the calm that defined her earlier innings here and which is a trademark of not only her game, but that of this entire Australian team.
"She's incredible and she has a phenomenal record in chasing as well," Jonassen said. "She just knows the tempo to go at and she's quite an incredible manipulator of the field as well. It makes it quite tricky. I always find her one of the hardest people to bowl to in the nets, so it's always nice in international cricket when she's finally on my side.
"She was incredible. She really held that run chase together and allowed a lot of the others, like Tahlia McGrath and Ash Gardener when they teed off at different points as well, she was able to play that role and then equally hitting a few crucial boundaries at really important times as well. So yeah, she's just doing Beth Mooney things pretty much."
Australia made a few rare fielding errors in this match, but they held their nerve when it counted most, as they so often seem to do.
"It got quite tight there in the end, but an incredible spectacle," Jonassen said. "We knew we had the firepower in the sheds to be able to chase that down, it just happened that it was off the second-last ball.
"A big thing we speak about as a group and something we think is a real bonus of what we can all bring is that composure and that calmness under pressure, and in high-pressure moments. So even though there were probably a few nerves internally… trying to not show it on the outside and to trust and to back your skills and your preparation and know that you've been there many times before. It's sport, it can be cruel, sometimes you come off second best; but we've found as a group, the more calm and composed we've stayed, we've generally come out on top."
Jones was one of only three England batters to reach double figures, her 40 from 21 balls was crucial after Sophia Dunkley scored a half-century and Heather Knight scored 29 off 22. Ecclestone, Lauren Bell and Sarah Glenn all claimed two wickets each and Jones believes England are closing the gap on this Australian side.
"Mooney batted really well and to have a batter bat the whole way through, you give yourself the best chance really, so I think she was probably the difference there," Jones said. "The gap feels like it's closing. They've earned the right to have all those compliments and they have been formidable really over the last few years. We felt like underdogs the whole way through but I think the Test match and today, the confidence is growing and it feels to us as if the gap is closing and that's a really exciting feeling amongst us."
For Jones' part, she will be hoping to maintain the form which saw her produce an innings that was "up there" in terms of personal highlights, having switched her focus from the Test, in which she scored 13 and 4 and moved to a more instinctive mindset under head coach Jon Lewis.
"I just refocused on what works for me in that in this format, resetting and thinking about those things really helped me," Jones said. "That's how I want to go out and play every game, so I think when it does come off I can take a lot of confidence from that for sure. If something creeps into my head - if I want to reverse, just reverse - no doubt. If something pops in just go for it, reminding myself of that."
England left out quick Issy Wong for the match on her home Edgbaston pitch, which was prepared by an all-female ground staff and offered good pace and carry. She was released from the T20 squad to play in the final 50-over match between England A and Australia A on Sunday with the Australians having won the first two fixtures.
Valkerie Baynes is a general editor, women's cricket, at ESPNcricinfo