How do I play as gritty in NHL 20 threes?

I am a huge flyers fan and played the threes circuit thinking I could unlock Gritty there..., to my surprise he was not an unlock able option as a mascot for the Philadelphia Flyers. I have unlocked him in ones, but really just want to be able to play with him on the Eastern Conference mascots team. Does anyone know how to unlock gritty to be played in offline threes? Thanks!