  In this paper, we define and study unstable measure theoretic pressure for
C^1-smooth partially hyperbolic diffeomorphisms with sub-additive potentials.
For any ergodic measure, we show that this unstable metric pressure equals the
corresponding unstable measure theoretic entropy plus the Lyapunov exponents
with respect to the ergodic measure. On the other hand, we also define unstable
topological and metric pressure in terms of the Bowen's picture and the
capacity picture. We show that all these definitions of unstable metric
pressure actually coincide for any ergodic measure.
