Mariona Caldentey's late penalty saw Arsenal snatch top spot in Group C from Bayern Munich, who they beat 3-2 on a dramatic night in the Women's Champions League at Meadow Park.
With both teams already through to the knockout stages, Renee Slegers' side knew only a victory would be enough to secure automatic seeding in the quarter-finals.
The hosts made an ideal start - just seven minutes had elapsed when Glodis Vigosdottir turned Caitlin Foord's corner into her own net.
Magdalena Eriksson levelled for the visitors six minutes before half-time, while she completed the turnaround in the 58th minute.
However, Arsenal responded within two minutes as Alessia Russo volleyed in Katie McCabe's corner, and they were awarded a penalty in the 85th minute when Tuva Hansen was adjudged to have handled Caldentey's shot.
The Spaniard, who missed from 12 yards against Liverpool last weekend, made no mistake this time around, sending Ena Mahmutovic the wrong way to secure top spot in Group C.
In the other game, Juventus salvaged some pride with a commanding 3-0 win over Valerenga.
Valentina Bergamaschi gave them a sixth-minute lead, and Juve did not look back after that. Sofia Cantore and Emma Kullberg then made sure of all three points in the second half, with their visitors finishing the group without a win.
A BIG THREE POINTS TO CLOSE OUT 2024pic.twitter.com/fSKZ7LNHQ1
— Arsenal Women (@ArsenalWFC) December 18, 2024
However, Manchester City surrendered top spot in Group D following a 3-0 defeat by Barcelona.
Barca needed to win to usurp City and, after dominating for much of the first half, broke the deadlock just before half-time through Claudia Pina.
Aitana Bonmati - recently crowned FIFA Best Women's Player of the Year - doubled the lead in the 57th minute, while substitute Alexia Putellas' 20-yard strike sealed the victory 12 minutes later.
Hammarby finished third place in that group with a narrow 2-1 win over St Polten, who exit the tournament having amassed no points following six straight defeats after failing to mount a late comeback despite Kamila Dubcova's goal.