T2w-MRI plays an important role in prostate cancer providing information on the location/grade in diagnosis or surveillance. T2-mapping may provide objective characterization but is hampered by long acquisition time, which has been addressed by dedicated acceleration techniques (e.g. kt-T2 mapping). We investigate further acceleration of T2-mapping by prospective variable sub-sampling in the echo time domain, comparing regular or irregular patterns in combination with compressed sensing using low rank and sparsity constraints, towards a routine clinical T2 mapping protocol with increased volume coverage. Prostate and phantom T2-maps with 24 slices (1×1×3mm3 voxel) were acquired in 5½ minutes with promising map quality.