Eflin was recalled from Triple-A Lehigh Valley on Monday, Todd Zolecki of MLB.com reports.
Eflin was already confirmed as Tuesday's starter, but this move officially allows the Phillies to utilize him in the majors. He'll take on Jarlin Garcia and the Marlins in his 2018 big-league debut. To make room for him on the active roster, Victor Arano (shoulder) was placed on the disabled list.