Champions Chelsea slumped to a 2-1 defeat away to newly promoted Liverpool last week, but Fran Kirby's first-half strike and a second-half penalty from Maren Mjelde were enough to get them back on track against City in front of more than 4,000 fans at their Kingsmeadow home ground.
Meanwhile, Everton inflicted a damaging Merseyside derby loss on Liverpool as they ran rampant at Anfield, winning 3-0.
Megan Finnigan got the visitors off to the perfect start with her ninth-minute header before Jess Park showed impressive composure to take the ball past Rachael Laws and slot past the Liverpool keeper in the 33rd minute.
Hanna Bennison added a third in the 87th minute after Liverpool's defence had been split open to ensure Everton got their first points of the season after losing their opening game 1-0 to West Ham United.
Brighton & Hove Albion also notched their first win at the second attempt, beating Reading 2-1 to send them to the bottom of the table, while Manchester United climbed into second place with a comfortable 2-0 win away at West Ham.
Liverpool host Everton in the season's first Merseyside derby later on Sunday.