Morales will have his contract selected from Triple-A Rochester prior to Tuesday's game against Atlanta, Yordano Carmona of Pelota Cubana USA reports.
Morales has put together a strong campaign at Triple-A, where he's hitting .286 with 25 home runs, 76 RBI, six stolen bases and 82 runs over 104 games. The 24-year-old's promotion will be made official Tuesday when rosters expand. Morales made 47 starts at first base, 40 starts at the hot corner and 17 starts as the designated hitter for the Red Wings this season, so he'll likely have a few different paths to playing time with the Nationals.