Walden signed a minor-league contract with the Mariners on Monday.
Walden agreed to a minor-league contract with the Brewers on Wednesday, Joel Sherman of the New York Post reports.
Walden signed a minor-league contract with the Cubs on Thursday.
The Red Sox released Walden on Saturday.
The Red Sox outrighted Walden to Triple-A Worcester on Monday, Pete Abraham of The Boston Globe reports.
Walden was designated for assignment by the Red Sox on Wednesday.
Walden was recalled by the Red Sox on Thursday.
Walden was optioned to the Red Sox's alternate training site Wednesday, Chris Cotillo of The Springfield Republican reports.
Walden is expected to be a member of the bullpen when the regular season begins, Chris Cotillo of MLB.com reports.
Walden earned the save Tuesday versus the Rays by recording one out and issuing one walk. He did not record a strikeout.