Basketball:who is the second most important player for the MAVS?

Normally, it's Kidd or Terry because the Mavs are a team that relies on outscoring people, and Kidd's their only true pass first point guard while Terry is the second go to scorer behind Nowitzki. But in the finals, I think it may be Marion. How well he's able to guard LeBron will be a huge factor in who win the title.