The Cats (4-1) retained a top-four spot, scoring a fourth-straight victory and their first in seven attempts against the Crows (2-3), with a 8.9 (57) to 6.10 (46) win at Adelaide's Unley Oval.
Gun midfielder Prespakis was dynamic for Geelong, racking up match highs of 32 disposals, 19 contested possessions and nine clearances.
In Perth, West Coast (1-4) posted their first win of the season in a 6.10 (46) to 6.5 (41) victory over Brisbane (2-3) at Perth's Mineral Resources Park.
It was their first AFLW win over the Lions in four attempts after three heavy defeats.
Young Eagles superstar Roberts put in a mammoth performance, leading the game In possessions, (33), contested possessions (19), clearances (11), tackles (eight) and metres gained (700).
In Adelaide, the Crows were up by four points after kicking the only goal of the first quarter, but Geelong hit back to lead by 15 and 26 at the end of the middle quarters.
The Crows notched the last six scores of the match, to slash a 32-point deficit to 11 with just under four minutes left.
They had 13 of the 15 inside 50s in the last quarter and Geelong's Bryde O'Rourke took a couple of clutch marks in the last minute deep inside their defensive 50 to secure the win.
"We knew they were going to bring the pressure all game and I thought we did really well at riding the momentum swings," Prespakis told Fox and Kayo.
"It's something we haven't previously done so well."
Former Crow Chloe Scheer, Julia Crockett-Grills and Jacqueline Parry all kicked two goals for Geelong.
India Rasheed and Grace Kelly both booted two goals for Adelaide.
The Cats' defensive 50 chains earned them 31 points and they also converted intercepts into multiple goals, with their slick handballs a point of difference.
Aisling Moloney was dangerous for Geelong and her Irish compatriot Niamh Kelly of Adelaide provided the highlight for the match, goaling after three bounces.
Crows stalwart Ebony Marinoff battled hard, accruing team-bests of 28 possessions and nine clearances and a match-high 11 tackles.
In Perth, Brisbane led for less than two minutes of the match, with West Coast up by eight, three and 11, at the three breaks
The Eagles racked up more clearances, contested possessions and tackles and Brisbane struggled to manufacture scoring opportunities.
Amy Franklin and co-captain Isabella Lewis each kicked two goals for West Coast.
"We went into the game thinking we could do it, every single one of us believed and I think that's what got us there in the end," Roberts told Fox and Kayo.
"It's kind of been coming. I felt like we've been building towards it, and to finally get the reward against a really quality team is amazing."
10°C