The Bruins continued to fill out their organizational depth on Friday, re-signing two defenseman who will most likely start the season in Providence.

The B’s signed 24-year-old Michael Callahan and 23-year-old Alec Regula to identical one-year, two-way contracts with NHL cap hits of $775,000.

Callahan, a Franklin native and Providence College product, played 70 games for the P-Bruins with four goals and 13 assists.

Regula, who came to the B’s organization in the Taylor Hall trade, had fur goals and 22 assists, along with a plus-36 rating, in 55 games for Providence last season.

Right  now after the signing of Nikita Zadorov, the B’s appear all but set at the varsity level with Zadorov, Hampus Lindholm and Mason Lohrei on the left side and Charlie McAvoy, Brandon Carlo and Andrew Peeke on the right with Parker Wotherspoon as the seven D-man. But Callahan, a left shot, and Regula, a right shot, could  be at the top of the list for call-ups if/when injuries strike.