While contending NBA teams are tipping off their postseasons, the disappointing Nets already have started their offseason.

General manager Sean Marks has eschewed talking to the media, and the team hasn’t offered any clarity on when he may do so.

But he did invite a group of season-ticket holders from the BK Block — fans from among the Brooklyn Brigade — to the HSS Training Center this week for a Q&A session.

And some of his answers to their questions backed up what The Post has been reporting: Despite the breakup of the ill-fated Big 3, the Nets are firmly convinced top players will still want to come to Brooklyn.