PORT ST. LUCIE – Johan Santana expressed shock yesterday at the report that Alex Rodriguez had used steroids at least through 2003.

Santana spoke before A-Rod confessed yesterday afternoon to using steroids in an interview with ESPN’s Peter Gammons after SI.com’s bombshell report last weekend.

“I was surprised to hear about it, just like everybody else,” Santana told The Post. “It’s a tough situation. You just have to let him give his side of the story and go from there.”

ALEX DROPS A-BOMB: I LIED

SHERMAN: ON ‘ROID TO RUIN OR RECOVERY

DISGUSTED FANS ARE CALLING IT FOUL BALL

COMPLETE YANKEES COVERAGE

PHOTOS: ALEX RODRIGUEZ

PHOTOS: ALLEGED STEROID USERS

Several other Mets already are here working out in advance of pitchers and catchers reporting on Friday, but prominent regulars on hand such as David Wright, John Maine and Mike Pelfrey were unavailable for comment on the Rodriguez story.