One day after Johan Santana threw a bullpen for the first time in 10 days, manager Terry Collins called it "unnecessary" and said he wished his ace handled himself differently.

"He’s fine," Collins said, "and he wanted to show everybody he was fine. I just said, ‘Look, we’re going to do this the right way. We’re not going to hurt you. … I don’t care how upset you are about things. We’re going to do this the proper way.’"

Santana was seething Sunday morning after general manager Sandy Alderson told CBS Sports that Santana reported to camp out of shape. He threw an unscheduled 15-to-20 pitch bullpen session. Collins said he told Santana he needs to let some things roll off his back rather than allowing them to jeopardize his health.

On Monday morning, Santana was as brusque with reporters as he was Sunday morning, but acknowledged his left arm was OK.

"Good," Santana said on his way out to practice. "That’s it, guys. Good."

Jeremy Hefner, the sixth arm in a five-man rotation, made a case that he deserves the final slot if staff ace Santana is unable to pitch come April. Hefner tossed three innings of one-run ball in a 4-2 loss to the Atlanta Braves on Monday afternoon.

"First and foremost, I want Johan to be healthy," Hefner said. "He’s a leader of this team. If something happens and he’s not able to go, then obviously that would maybe fall on my shoulders. I’m going to prepare to go out and give it my best whenever my name’s called."