Chelsea beat Real Madrid 2-0 in the Women's Champions League on Wednesday, while Paris Saint-Germain finally got their campaign up and running with a comfortable 5-0 win over Group A minnows Vllaznia.
Chelsea had the better chances in the first half and dominated the wide areas, but struggled to find their edge in front of goal with Las Blancas doing just enough in the box to keep them out.
Largely quiet in attack before the break, Madrid came out with renewed vigor in London to begin to challenge Ann-Katrin Berger's clean sheet, but the game reamined deadlocked before Chelsea found their breakthrough after the hour.
With their strikers struggling for purchase, the onus moved to those further back the pitch with Millie Bright nodding Erin Cuthbert's corner on for Sophie Ingle to head home at the back post.
Chelsea got their second when Cuthbert raced down the wing and miss-hit her cross, but the midfielder had the perfect view to watch it arc across the crossbar before dropping into the far side of the net.
The goal took the wind out of Madrid's sails and left them chasing shadows for the last 10 minutes and the result left Chelsea in a comfortable position atop Group A on nine points, five ahead of PSG.
In the earlier window, PSG finally scored their first goal of this season's competition after 219 minutes of football when Grace Geyoro chipped the ball over Vllaznia keeper Kaylin Williams-Mosier.
One became two five minutes later when Matilda Gjergji flicked Sakina Karchaoui's low ball beyond her own keeper before Ramona Bachmann added a third for PSG from the spot.
Sandie Baltimore made it four with a vicious strike to beat Williams-Mosier at her near post and 19-year-old Magnaba Folquet tucked home Ashley Lawrence's through ball in the 85th minute to reach the final scoreline.
Elsewhere on the night, Austrian champions St. Polten snatched a vital 1-0 win over fellow group stragglers Slavia Prague when Maria Mikolajova curled home a striker from outside the box in second half stoppage time.
Even with the win, St. Polten couldn't break into the top two in Group B with leaders Wolfsburg earning a 1-1 draw with Roma in the late kickoff of the day.
Despite looking like they could go all the way this season, the German champions were given a stern test in Italy and had to rally to come from a goal down after Valentina Giacinti swept the ball home from the top of the box in the third minute for Roma.
The advantage lasted for 30 minutes before the visitors resorted parity as Ewa Pajor skipped into the box, leaving Elena Linari on the deck, before wrapping the ball beyond Roma keeper Emma Lind.
On what was a closely contested match just outside of Rome, the She Wolves failed to find a second goal to keep their 100% record in the group intact and can now only boast an advantage in the standings on goal difference as both teams ended the day on seven points from three games.