  We considered the power corrections to the amplitude describing hard
exclusive pion pair production in gamma gamma collisions at large energy and
momentum transfer. In order to derive a factorization formula for the
subleading power corrections one has to take into account the so-called
soft-overlap (or soft) contributions. These terms can be naturally introduced
within the SCET framework as a matrix elements of the SCET-I operators. The
so-called end-point singularities must cancel in the sum of the hard and soft
contributions after matching onto SCET-II. Using the so-called physical
subtraction scheme we demonstrated such a cancellation in the case of twist-3
chiral enhanced contributions in the leading logarithmic approximation.
  As a result we obtained the well defined expression for the subleading power
correction which depends only from the two unknown functions. These functions
can be associated with the soft-overlap of the outgoing pion state and
therefore does not depend on the scattering angle. The angular dependence in
this case is defined by the hard subprocess and can be computed in a model
independent way.
  The obtained results were used in the phenomenological analysis of existing
data. We showed that using the leading and subleading contributions and
considering the unknown functions as a free parameters one can describe
consistently the data for $\pi^{+}\pi^{-}$ and $\pi^{0}\pi^{0}$ production.
