The Etihad Stadium home to the City men was being used for the season opener rather than the smaller nearby stadium usually used by the women's team, as WSL teams look to build on the popularity of the Women's World Cup where England reached the semifinals.
"This was an occasion for us to showcase the women's team in a Manchester derby," City manager Nick Cushing said. "But our home stadium is the academy stadium and hopefully we can drive a lot of those people there.
"We just want to see that crowd that we see in the Etihad Stadium week after week pushing the men's team crossing over. We're excited to see what happens with our crowds and where they go." While City was second in the WSL last season and won both domestic cups, United is in the topflight for the first time after being promoted as Championship winners. United disbanded its women's team in 2005 but it was reformed last year.
The previous WSL attendance record was the 5,265 who saw Arsenal win the title at Brighton last season, although Chelsea's London derby with Tottenham on Sunday is expected to raise the bar further. All tickets in the 40,000-capacity Stamford Bridge have been distributed for free.
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