Sullivan would likely take over for offensive coordinator Kevin Gilbride, who announced his retirement last week.
Sullivan was the Giants wide receivers and later, quarterbacks coach, before becoming Tampa Bay's offensive coordinator under Greg Schiano.
The Giants never wander too far astray when looking to bring in coaches and players. Anyone they sign is usually a known entity who had a relationship with either the team or one of the coaches.
Such is the case with Sullivan, a Tom Coughlin (and Kevin Gilbride) disciple who is a former West Pointer that knows his way around QDTC. How much of a stretch he will be from Gilbride is questionable. I'm guessing not much.