Evolutionary tracks in the HR diagram during core hydrogen burning for models with initial masses between 9−300 M_⊙ (see labels) and initial rotational velocities of 0, 200, 350 and 500 km s^-1, with a composition of 1/10 Z_SMC. The lighter (purple) shading identifies the region in which all models of our grid undergo core hydrogen burning. The darker (green) shading identifies the zero-age main-sequence. An arrow marks the end of the tracks for models that were stopped before the terminal age main-sequence was reached. Core-hydrogen-burning objects are expected to be found on both sides of the ZAMS, inside the purple coloured region.