A seven-wicket by Djali Bloomfield left the Vikings stunned at 50 overs as Weston Creek-Molonglo start to gain momentum leading into the Douglas Cup finals.
Bloomfield took 7/20 with four maidens to put Creek in the box seat of Saturday's date with Tuggeranong Valley at Chisholm Oval.
The 28-year-old quick claimed the all-important wicket of Craig Devoy (9) to put the hosts under pressure early, before rolling through their tail end to keep their total to 119.
David Waters bowled six overs for seven runs to keep the economy rate tight, while Joe Slater took the opening wicket of Matt Rogers.
"The deck wasn't too bad, we were getting out to swing early," Bloomfield said.
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"They batted okay and got off to a reasonable start, I managed to come back on at the end and roll through them a little bit easier than what we were hoping for even.
"In the one-day final a few weeks ago, Devoy set the tone of the match. He was by far the best batsman for both teams and managed to get them off to a flyer.
"Seeing him back in the shed early probably put pressure on some of the younger guys, we managed to roll through them after that.
"It was helpful with everyone keeping it tight, 50 runs for 119 is a really good economy."
Creek's Robbie Trickett hardened the blow with an 85-run haul, which included nine four's and three sixes.
The visitors finished the day 5/169 with Joshua Low-McMahon 54 not out from 65 balls, having hit 11 boundaries.
After winning the first innings, Creek will look to claim an outright victory over the ladder-leading Vikings next weekend.
"We're in a good position," Bloomfield said.
Eastlake kept North Canberra-Gungahlin to just 99 runs at Kingston Oval thanks to Nicholas Wood's wicket haul of 3/19, while Western District declared 9/306 against Ginninderra - with Scott Murn leading the charge with a score of 95.
Across the border, Dan Leerdam blasted 80 runs to lead ANU to a 270-run total against Queanbeyan at Freebody Oval. The hosts then posted 2/7 at stumps.