Chelsea's new additions, including Katie McCabe and Melvine Malard, proved to be the difference in the match. McCabe, who joined from Arsenal in a high-profile move, delivered a dangerous corner that Naomi Girma delicately tapped home to level the score. Malard, who joined from Manchester United for an £800,000 transfer fee, struck twice to wrestle control of the tie back from the Spanish side.
Chelsea's lack of a traditional preseason was particularly evident in the final third, but the introduction of Malard changed the contest. The French forward's goals helped turn a precarious tie into a commanding advantage. James completed the scoring spectacularly, smashing Ellie Carpenter's pinpoint cross into the roof of the net to make it 5-2.
Chelsea will now travel to Spain next Wednesday for the second leg of the tie, before their domestic campaign kickstarts the following Saturday.