Smith signed a one-year contract with the Red Sox on Wednesday, Gabrielle Starr of the Boston Herald reports.
Smith slashed .263/.337/.375 across 89 plate appearances with the Rays' Triple-A affiliate while on a minor-league deal. He was released by Tampa Bay earlier on Wednesday and will now join the Red Sox on a major-league deal to help make up for the loss of Triston Casas (ribs). Smith will likely end up splitting time with Garrett Cooper (wrist) at first base, replacing Bobby Dalbec.