Shaw's contract was selected by the Red Sox on Thursday, Rob Bradford of WEEI.com reports.
Shaw joined the Red Sox as a non-roster invitee and has secured what will likely be a bench spot in Boston. The last time Shaw finished with an above-average batting line was 2018, though he did post a 122 wRC+ in a tiny sample of 48 plate appearances for the Red Sox last year after struggling earlier in the season with the Brewers.