Manager Paul Molitor made the announcement after Thursday night's 4-1 loss to the New York Yankees. Santana missed 16 games with a strained left hamstring and was on a rehab assignment with Triple-A Rochester. He can play all three outfield positions plus shortstop and second base.
Arcia started 27 of 61 games this season, playing both corner outfield spots, but the 25-year-old had only 11 at-bats in 15 games this month. With eight relief pitchers on the roster, Molitor desired more versatility on the bench.
Arcia could be assigned to Triple-A, but other major league teams have the chance to claim him first.
Arcia hit 20 homers in 372 at-bats in 2014.