TARRYTOWN, N.Y. -- While there were no hitters and no catcher -- and, really, no real pitches -- Mariano Rivera climbed back atop a mound on Friday for the first time since his season-ending injury, tossing some prop baseballs as part of a commercial shoot.

"I'm feeling good," said Rivera, who made about 25 throws on the Hackley School's snow-covered diamond. "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."

Rivera, who turns 43 later this month, flashed his smooth, iconic form as he lobbed the baseballs toward a protected cameraman, showing no ill effects from a torn right anterior cruciate ligament, an injury that truncated his season in May.

One week ago, Rivera told general manager Brian Cashman that he decided to continue pitching in 2013. Currently a free agent after the expiration of his two-year, $30 million deal, Rivera is leaving negotiations in the hands of Cashman and agent Fernando Cuza.

"Like I told you guys before, I didn't want to go out like that," Rivera said. "At the same time, we haven't discussed anything. We're talking, so hopefully we'll finalize everything."

But with months to go until the Spring Training report date for pitchers and catchers, Rivera is in no hurry to push his rehab to the next level, no matter how good it might have looked to see him back on a mound.

"I have a long time to go. I'm not rushing," he said. "I just have to make sure that my knee gets stronger. It does. It's getting stronger and stronger every day. I'm happy with that. I just have to continue what I'm doing."