Tekashi69's manager appears to be off the hook for the Barclays Center shooting last month -- 'cause cops arrested a different alleged member of 6ix9ine's crew for that one.
Law enforcement sources tell TMZ cops arrested Fuguan Lovick on Sunday, and booked him for first-degree reckless endangerment for a shooting inside the Brooklyn arena during a recent Adrien Broner boxing match.
We broke the story ... Tekashi's group got into a scuffle with a rival rap crew, and cops believe someone in his camp fired a weapon.