In this work we studied transport properties of eutectic InSb-MnSb crystals with oriented MnSb needle-like inclusions under a hydrostatic pressure up to P = 8 GPa and after its application. We show that the pressure-induced variation of the samples resistivity and transport parameters at room temperature can be interpreted in the terms of crystal phase transition of the InSb matrix. We argue that the irreversibility of this transition, deduced from transport measurements, may stem from the composite nature of the crystals studied. The resistivity of the samples subjected to high pressures increases upon cooling, which can be a consequence of the increased disorder accompanying the irreversible transition. Magnetotransport data for these samples suggest that charge carriers interact with a low-temperature magnetic phase. The latter can be formed by isolated Mn atoms in the InSb matrix.
