Compensation talks between the two teams for Farrell's services came down to either Aviles or Red Sox closer Andrew Bailey, according to ESPN's Buster Olney, although it's unclear how the two clubs ultimately decided on Aviles.
Olney notes that by adding Aviles, the Jays will have more flexibility in deciding how to move forward with Yunel Escobar. Escobar earned the team's ire last season by wearing a homophobic message on his eye black, and with Aviles proving himself capable at the position last year, the Jays could be looking to move the young shortstop.
Bailey took over as closer for Boston last year after an injury kept him out for most of the season, but he by no means solidified himself in that role. The right-hander was just 6-for-9 in save opportunities and posted a 7.04 ERA on the season.