Casas (rib) was upbeat Tuesday when discussing the progress he's made while on rehab, Ian Browne of MLB.com reports.

The Red Sox transferred Casas (ribs) to the 60-day injured list Saturday, Andrew Destin of the Pittsburgh Post-Gazette reports.

Casas revealed Friday that he's dealing with torn cartilage in his left ribcage, not a fractured rib as had been previously reported, Alex Speier of The Boston Globe reports.

Red Sox manager Alex Cora said Tuesday that Casas has been diagnosed with a fracture in his left ribcage and will be "out a while," Chris Cotillo of The Springfield Republican reports.

Casas (rib) underwent an MRI on Monday that confirmed the expectation that he'll be out for significant length of time, Julian McWilliams of The Boston Globe reports.

The Red Sox placed Casas on the 10-day injured list Sunday with a left rib strain, Mac Cerullo of the Boston Herald reports.

Red Sox manager Alex Cora said Saturday that Casas is undergoing tests for a rib injury, Chris Cotillo of The Springfield Republican reports.

Casas left Saturday's game against Pittsburgh due to left rib discomfort, Chris Cotillo of The Springfield Republican reports.

Casas was removed from Saturday's game against the Pirates due to an apparent injury, Chris Cotillo of The Springfield Republican reports.

Casas went 1-for-4 with a walk and a solo home run in Friday's 8-1 win over the Pirates.