Duffy (ankle) will start at third base and bat second for Sunday's game at Minnesota, Marc Topkin of the Tampa Bay Times reports.
Duffy left Saturday's game with the injury after appearing to roll his ankle on a swing but won't be held out of Sunday's lineup. If there were any concern from the Rays, they would undoubtedly give the 27-year-old an additional day of rest leading into the All-Star break, which bodes well for the severity of the injury.