The 34-year-old Francis is expected to join the Bisons on Friday. He appeared in eight games for the Blue Jays and allowed nine earned runs over 12 innings as he primarily worked as the club's long reliever.
Toronto also signed outfielder Alex Hassan to a Minor League contract on Wednesday afternoon. Hassan previously spent time this season with the Rangers and A's Triple-A affiliates after appearing in 114 games for Boston's Triple-A Pawtucket in 2014.
Hassan, 27, is a former 20th-round pick by the Red Sox from the 2009 Draft. He's appeared in parts of seven Minor League seasons with a .288 average and .824 OPS.
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, follow him on Twitter @gregorMLB and Facebook, and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.