The syringe of cortisone that invaded Derek Jeter’s left ankle Wednesday deleted a degree of soreness from the hinge. While that is a positive sign, the Yankees are taking steps to make sure that if Jeter lands on the disabled list he can be backdated. Whatever games Jeter plays in before camp concludes Thursday will be minor league tilts. They don’t count in the backdate scenario because admission isn’t charged. A player can only be backdated to March 22. If that happens a player can’t come off the disabled list until April 6. “We need to preserve the ability to backdate him,’’ said general manager Brian Cashman, who also said it was possible for Jeter to be ready by Opening Day. When Jeter was scratched from Tuesday’s game against the Phillies because of stiffness in the front of the ankle he fractured last October and had surgery on, it was considered by some as a setback. Ditto for when Jeter was injected with cortisone Wednesday. Nevertheless, Jeter doesn’t view it that way and is going to participate in limited baseball activities today. “We will see if he gets on the field [today],’’ manager Joe Girardi said . “Hit and go through drills and see where we are at.’’ Jeter said the original goal of being ready to play April 1 remains intact.