Aoba Fujino already has three goals this season, having scored four in 2024-25.
At a glance
Aoba Fujino scores only goal in first half
West Ham's Viviane Asseyi and City's Gracie Prior both hit crossbar
City stay second, a point behind leaders Chelsea
Manchester City had to battle hard to beat bottom-of-the-table West Ham, with Aoba Fujino's goal sealing a sixth successive Women's Super League win.
The Japan international struck in the 26th minute, with her third goal of the season condemning struggling West Ham to a ninth successive defeat and losses in all seven league games this term.
Second-placed City were far from fluent in their display, but did enough to claim the victory that kept them one point behind leaders Chelsea.
Rehanne Skinner's Hammers, though, put in a committed performance that belied their lowly status, with Viviane Asseyi going closest to scoring when her shot hit the crossbar just before half-time.
City defender Gracie Prior also headed against the woodwork in the second half, but the hosts gave West Ham opportunities.
Riko Ueki missed out with a great chance when her shot was saved by keeper Ayaka Yamashita, while striker Shekiera Martinez had a shot blocked by Prior after a mistake by Laura Blindkilde Brown.
City pressed for a second to ease their nerves, but Amber Tysiak threw herself in front of a Bunny Shaw effort, while the City striker had another shot blocked late in the game, with Prior's follow-up also kept out by the spirited visiting defence.
Analysis: City lack ruthlessness as Hammers show fight
City had nine shots to West Ham's five in an exciting first half, but a tally of just one each on target highlighted a lack of composure in front of goal from both sides.
The defences looked brittle under pressure too, and Shelina Zadorsky's mistake in her own half resulted in the winning goal, as Vivianne Miedema broke to set up Fujino, who slid her finish across Kinga Szemik.
But despite their awful run of results and without a goal in their previous three outings, West Ham did not hide with a positive approach amid tentative defending from Andree Jeglertz's side.
Ueki should have scored, but fired straight at the legs of her Japan team-mate Yamashita, while Asseyi blazed a volley wide following good work on the right from Ffion Morgan.
The busy Asseyi nearly made amends when she lifted the ball over Yamashita from close range, only to see her strike rebound off the crossbar.
City applied more pressure following that close call, with Shaw and Miedema thwarted by committed defending from Yu Endo, Oona Siren and Asseyi that typified West Ham's performance without the ball.
Prior's thumping header almost made it 2-0, while Skinner's side repeatedly put their bodies on the line.
Despite extending their winning run, City will need to be more ruthless in front of goal if they are to maintain their title challenge as they could be punished by better sides.
West Ham will take heart from their competitive display but desperately need a first WSL point since April.
What's next for these teams?
West Ham host Leicester City on Sunday, 9 November (12:00 GMT), while Man City visit Everton on the same day (14:30 GMT).
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