Johan Santana had a “secret” throwing session this morning in Port St. Lucie, according to Jon Heyman of CBS Sports.

“Mets star Johan Santana threw this morning and felt well afterward, but the Mets are still taking it cautiously, so cautiously in fact that at least to this point it doesn’t seem to be public knowledege that he threw,” Heyman explains.

Santana threw from 45 and 60 feet today, from flat ground, according to the team’s beat reporters on Twitter.

Heyman says the Mets will be monitoring Santana closely after today’s session, and there is still no timetable as to when or if Santana will appear in a Grapefruit League.

Michael Baron, MetsBlog.com:

Anytime Santana throws without incident – be it off flat ground or off a mound – that’s progress at this point. But even though he feels good now, Santana clearly still has a long way to go. I’m assuming Santana will start the season on the disabled list – that would allow him to stay back in Port St. Lucie for an extra week and continue to get stronger. But there’s no telling what’s going to transpire between now and then, how he’s going to respond to each of his throwing sessions, when or if he’s going to start pitching in spring games, and so on.