Rivera turned 40 in November, a month that saw the Yankees celebrate their World Series victory after his final pitch of 2009 was chopped into Yankee Stadium's soft infield grass.
After a three-month respite following that Shane Victorino roller, Rivera was back to business on Monday in his first time back on a mound, throwing a breezy 21-pitch bullpen session under the watchful eyes of manager Joe Girardi and pitching coach Dave Eiland.
"I wasn't wild," Rivera said, with a smile. "For the first one, I'll take it. I'm OK with that."
They were the first pitches following a season that saw him perform just about as sharply as ever, appearing in 66 games and compiling a 1.76 ERA while converting 44 out of 46 save opportunities -- plus 12 more appearances and five saves in the postseason, further adding to his legend.
At times, it was easy to forget that Rivera's health had actually been a concern at this time last year in Spring Training, when he reported to camp having had arthroscopic surgery to shave down an arthritic AC joint in his right shoulder.
While the final results would never tell, Rivera admitted on Monday that he needed a little more time to get his prized pitching arm into shape last season.
"Any type of surgery that you have, it will take time to heal," Rivera said. "For me, it wasn't easy. I did all my rehabbing in the season. It was hard, but it wasn't impossible. I took the challenge, and it worked."
Girardi said that Rivera wasn't able to fully extend last spring and guessed that the hurler's motion wasn't right until six to eight weeks into the regular season. Watching Monday's session was preferable.
"It's a lot better feeling, that's for sure," Girardi said. "It was good to see him. The ball looked good coming out of his hand. Last year at times, he couldn't extend early on in camp, and he had none of those issues. It's great to see."
Rivera expects to throw three or four bullpen sessions before actually getting into a game somewhere around the midpoint of camp, which is standard operating procedure for him.
"The abbreviated springs have worked for him," Girardi said. "We don't feel it's necessary for him to get in games and get stretched out for two innings. We just don't feel that's necessary. He gets plenty of work during the season, so we'll keep it down here to a minimum."
And if anyone has an issue with that, Rivera can always point to his 39 postseason saves as proof that the formula is worth following.
"Throwing in the postseason all those years puts a lot of stress on your shoulder and your body," Rivera said. "I want to recuperate as long as I can, and make sure that when I come to Spring Training, I do what I have to do to be ready for the whole season."
Last season, Rivera made it into Grapefruit League duty for a grand total of seven innings, and there's little reason to anticipate he'll pitch much more in 2010.
"After you throw nine, 10, 11 innings, what is there to do?" Rivera said. "If you're ready, you're ready."