  Infinite projected entangled pair states simulations of the $S=1$
bilinear-biquadratic Heisenberg model on the square lattice reveal an emergent
Haldane phase in between the previously predicted antiferromagnetic and
3-sublattice 120$^\circ$ magnetically ordered phases. This intermediate phase
preserves SU(2) spin and translational symmetry but breaks lattice rotational
symmetry, and it can be adiabatically connected to the Haldane phase of
decoupled $S=1$ chains. Our results contradict previous studies which found a
direct transition between the two magnetically ordered states.
