Professor Saul Rubichik was an instructor at Starfleet Academy in the late 24th century. He died prior to stardate 57752.6.
On one occasion, Cadets Beckett Mariner and Amina Ramsey stole Rubichik's "old, special car" and drove it into San Francisco Bay. Mariner remembered the mischief fondly, including how angry it made Rubichik.
Ottessa Warren noted that Rubichik served as her mentor at the academy, and that she had even spoken at his funeral. (LD: "Much Ado About Boimler")
This character was only mentioned in dialogue.