Arsenal defender Pablo Marí underwent surgery on his back on Friday to fix injuries suffered in a horrifying knife attack ... but, thankfully, his team says he's now doing well.
A.C. Monza -- the club for which Pablo is playing while on loan for Arsenal -- said the procedure entailed repairing two torn muscles. They added, "the operation went well."
The club also said the 29-year-old will need to remain in the hospital this weekend ... and is expected to be out of action for two months as he recovers.