Irsay faces four felony counts of possession of a controlled substance having been arrested on suspicion of intoxicated driving late last Sunday.
The 54-year-old has since checked himself into a health-care facility, and Grigson revealed that the whole team was rooting for him to make a full recovery.
"Obviously nothing but great things to say about Jim, he's been magnificent and has done so much for myself, [coach] Chuck [Pagano], the entire building, everyone in the building loves the man," Grigson is quoted as saying by ESPN.
"We all would run through a brick wall for him. We all wish him a full, complete recovery and we're all pulling for him, and I'll leave it at that."
If convicted of the felony charges, Irsay could face a sentence of up to three years in prison on each count.