Mariano Rivera threw off a mound on Friday ... for a commercial shoot. After making 25 tosses, Rivera said he feels terrific, but won't rush his rehab, according to MLB.com. "I'm feeling good," said Rivera. "The rehab has been great; it's been tough, but at the same time, I'm seeing good results. I can't wait to continue and stay 100 percent. A day at a time, like I always tell you guys. A day at a time."