Cory Monteith's recent rehab stint might be affecting production at 'Glee,' but his costars understand that his health comes before the show -- and Mark Salling, for one, knows that what Monteith's going through requires large round objects.

"It takes balls ... to go through that publicly. Period," Salling told Us Weekly. "It takes balls to go through that privately, but to go through it publicly like that -- balls."

On April 1, Monteith announced he was voluntarily checking into rehab, signaling that his struggle with substance abuse -- which also included a stay in a treatment facility more than a decade ago -- has entered another difficult phase.

Salling, who went on to add that he and the rest of the cast are checking in on Monteith with "nice texts" and tweets "here and there," is the latest 'Glee' star to voice public support for their unwell comrade. As we previously reported, his off-screen sweetheart, Lea Michele, quickly issued a statement that read, "I love and support Cory and will stand by him through this. I am grateful and proud he made this decision."

The show's co-creator and executive producer, Ryan Murphy, told his Twitter followers, "I am so proud of Cory Monteith and love and support him 100%."

Get well see, Cory!