New result, as rapidity spectra, on proton and antiproton production in central Pb+Pb collisions at 20, 30, 40, 80 and 158 GeV from NA49 experiment at the CERN SPS will be presented. They will be shown for the first time. Their relation to the hypothesis of the onset of the deconfinement at low SPS energies will be discussed. The results will be compared to the results at lower (AGS) and higher (RHIC) energies.