ML service time is what determines arb. seasons.
He'll be "eligible" for arbitration as long as he's got between 3 and 6 seasons of ML service time.
If he has options, you can arb. him, and stach him in AAA (or AA, or wherever) on the DL. He won't accrue ML service time, keeping him from hitting the open market "early".
Considering the recent changes in the arbitration engine, I'd sign him to 1 year, and hope that being on the DL lowers his demands for next season.