Shaffer was released by the Indians on Wednesday.
Shaffer was named International League Player of the Week on Monday.
Shaffer went 2-for-4 with a grand slam, bumping his team-high RBI total to 43, in Triple-A Columbus' victory on Monday.
Shaffer was reassigned to the Indians' minor-league camp Sunday.
Shaffer is competing for an Opening Day roster spot at third base, Jordan Bastian of MLB.com reports.
Shaffer received an invitation to attend spring training.
The Indians designated Shaffer for assignment Monday, Paul Hoynes of Cleveland.com reports.
Shaffer was claimed off waivers by the Indians on Thursday.
Shaffer was claimed off waivers by the Reds on Friday.
Shaffer was designated for assignment by the Phillies on Tuesday.