TAMPA, Fla. -- This was certainly not Mariano Rivera's ninth-inning game face. Instead, there was the Yankees closer, with a broad grin spilling across his face as he went into his famous pitching motion on a sunny back field.

As Rivera threw his first live batting practice session of the spring Wednesday morning, the laughter told the Yankees that his surgically repaired right shoulder is holding up exactly as they had hoped.

"It's getting stronger," Rivera said. "Every time I throw, it's feeling better and better. I have no doubts."

Working to John Rodriguez and Jesus Montero, Rivera threw 30 pitches on a back field at the George M. Steinbrenner Field complex, showcasing his stuff in front of an audience comprised mostly of reporters and about two dozen fans.

It was Rivera's fourth mound session of the spring -- one of which was done in Puerto Rico, where he had traveled to support Panama's entry in the World Baseball Classic -- and the first with hitters in the box.

His command needed some refining, forcing Montero and Rodriguez to dodge several pitches each. But Rodriguez kept up constant chatter with a running play-by-play of the inside pitches, which made Rivera laugh, and Rivera said that he had expected some rust coming off his surgery.

Rivera said he worked at about 90 percent of his regular velocity. He will throw batting practice again Saturday, and believes he could pitch in his first game of the spring Monday at home against the Phillies.

"If it feels as good as it feels now, there will be a game," Rivera said. "Everything feels great."

Right-hander Edwar Ramirez also threw 30 pitches in a live batting practice session. He had missed time with right shoulder bursitis, but he said everything felt "good," and remains in the mix to break camp in a bullpen role this spring.