Santana agreed to a contract with the Yakult Swallows of Nippon Professional Baseball on Wednesday, Jon Morosi of MLB Network reports.
Santana's $5 million team option was declined by Cleveland on Friday, Zack Meisel of The Athletic reports.
Santana cleared waivers and was outrighted to the Indians alternate training site Friday.
The Indians designated Santana for assignment Monday.
Santana is not in Friday's lineup against the Cardinals.
Santana isn't in Wednesday's lineup against the Twins.
Santana isn't in the lineup for Monday's game against the Twins.
Santana went 1-for-4 with a double and three RBI on Saturday against the Tigers.
Santana went 1-for-4 with a double and three RBI on Wednesday against the Pirates.
Santana will start in left field and bat seventh Sunday against the Tigers.