Varvaro, 30, was designated for assignment by the Red Sox on April 29, and claimed off waivers by the Chicago Cubs on May 3. As a result of his medical condition on the date of his outright assignment to the Cubs, the severity of which was unknown to the Red Sox at the time of the assignment, both clubs agreed that it would be appropriate to return Varvaro to the Red Sox for placement on the disabled list in accordance with the major league rules.
Varvaro had made nine relief appearances for the Red Sox this season after being acquired in a trade with the Atlanta Braves on December 17, 2014. The right-hander was 0-1 with a 4.09 ERA (5 ER/11.0 IP) for Boston, allowing 14 hits and recording eight strikeouts against six walks. In parts of six major league seasons with Seattle (2010), Atlanta (2011-14), and Boston (2015), Varvaro is 7-9 with one save and a 3.23 ERA (66 ER/183.2 IP), recording 150 strikeouts and 70 walks in 166 appearances, all in relief. Originally selected by the Mariners in the 12th round of the 2005 June Draft, the Staten Island native is 14-38 with 29 saves and a 4.52 ERA (235 ER/467.2 IP) in 222 career minor league appearances (49 starts).
The Red Sox 40-man roster is now at 40.