Lindsey Horan's 49th-minute strike led the Portland Thorns to their second NWSL title after a hard fought clash in Orlando.
The US national team midfielder found herself unmarked at the back post off a set-piece after the ball slipped through the box, with Horan slamming home a half-volley from close range at Orlando City Stadium.
Portland, which previously won the title in the league's inaugural 2013 campaign, topped the NWSL Shield-winning Courage in a matchup of the top two teams from the regular season.
Raso in particular had been a key part of the west-coast side's drive to the championship, with her 6 goals and consistent performances earning her the Fan's Player of the Year.
She had a combative game up front for the Thorns, earning a yellow card for a late challenge, before being subbed in the 69th minute.
Sykes was also a regular member of the first team, often playing a bit deeper than Raso and fashioning chances for others. The midfielder found herself on the score sheet in a recent match against the Chicago Red Stars to ensurethe Thorns would make it through to the play-offs.
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