The Rangers will defer naming a captain to succeed Ryan Callahan until the offseason after playing the rest of the year with Brad Richards, Marc Staal and Dan Girardi wearing the alternate’s “A” on their jerseys.

General manager Glen Sather traded Callahan to the Lightning on Wednesday in exchange for their captain, Martin St. Louis, along with a first-round draft pick in 2015 and a second-rounder in 2014.
“Glen and I were just discussing that as we were coming up here,” coach Alain Vigneault said before his team lost to the Maple Leafs 3-2 in overtime at the Garden. “We’re going to leave it with three A’s for the remainder of the year and then deal with that this summer.”

Staal would be considered the front-runner to become captain next season if — and only if — the defenseman signs a contract extension over the summer and thus renounces pending 2015 free agency.

Indeed, the offer of the captaincy is likely to become part of the negotiations with Staal, who obviously has a pull toward Carolina, where his brothers Eric and Jordan play for the Hurricanes.

If Staal does not sign an extension, the captaincy could then be bestowed upon Richards (if he is not an amnesty buyout), Girardi or Ryan McDonagh.

The Blueshirts also addressed a need for depth on defense, picking up rental property in 28-year-old Raphael Diaz from the Canucks in exchange for a fifth-rounder in 2015.