Hanigan, 34, was placed on the 15-day disabled list on May 2 with a fractured right hand suffered on May 1 against the New York Yankees, transferring to the 60-day disabled list on May 3. The Andover, Mass., native appeared in seven games of a rehabilitation assignment, combining to hit .211 (4-for-19) with two runs scored, a double, and six walks in four games with Triple-A Pawtucket and three with Double-A Portland. With Boston this season, he has hit .222 (12-for-54) with 11 runs scored, two doubles, one home run, five RBI, and a .354 on-base percentage. Among active catchers with at least 500 games behind the plate, Hanigan, who caught two no-hitters with the Cincinnati Reds, ranks first in fielding percentage (.996) and third in catcher's ERA (3.64). In 577 career major league games with the Reds (2007-13), Tampa Bay Rays (2014), and Red Sox (2015), Hanigan has hit .255 (416-for-1,633) with 157 runs scored, 59 doubles, 26 home runs, and 177 RBI, throwing out 33 percent (99 of 198) of attempted base stealers.
In the first major league stint of his career, Aro, 24, appeared in three games for the Red Sox, debuting on June 25 against Baltimore. Over his three relief appearances, he had an 11.57 ERA (6 ER/4.2 IP) with three strikeouts. In 18 minor league appearances between Double-A Portland and Pawtucket this season, the right-hander is 3-2 with one save, a 2.22 ERA (11 ER), and 49 strikeouts in 44.2 innings, holding opponents to a .184 batting average (30-for-163) while allowing just 11 walks. In 10 games since being promoted to the PawSox on May 14, the Dominican native totaled 30 strikeouts and just three walks in 22.1 innings, posting a 1.61 ERA (1 ER). At the time of his promotion to Boston, he had an 18.0-inning scoreless streak over eight games with the PawSox. Signed by Boston as an international free agent in June 2011, Aro has gone 16-14 with 12 saves, a 2.68 ERA (81 ER/272.0 IP), and 268 strikeouts in 85 outings (12 starts) over parts of five minor league seasons in the Red Sox system. Prior to this season, he had never pitched above Single-A, spending most of 2014 with Greenville, where he was named a mid-season South Atlantic League All-Star.