The vector A y and tensor analyzing powers A yy and A xx for d p-elastic scattering were measured at T lab d = 880 MeV over the c.m. angular range from 60• to 140• at the JINR Nuclotron. The data are compared with predictions of different theoretical models based on the use of nucleon-nucleon forces only. The observed discrepancies of the measured analyzing powers from the calculations require the consideration of additional mechanisms.