Duffy (Achilles) was placed on the 60-day disabled list Thursday, Marc Topkin of the Tampa Bay Times reports.
The Rays needed to make room on the 40-man roster for Alexei Ramirez, so the Rays opted to send Duffy to the 60-day DL since he won't be back to playing until next season. The infielder is expected to undergo surgery on his injured Achilles tendon soon.