Romero helped the Phillies win the 2008 World Series, earning two wins out of the bullpen against the Tampa Bay Rays. He had a 3.86 ERA in 24 appearances this season.
Worley is 2-1 with a 3.75 ERA this season for the Phillies. He was recalled from Triple-A Lehigh Valley and will start at Seattle on Saturday.
Romero joined the Phillies in 2007. He was 6-6 with four saves and a 2.73 ERA in 237 games.