The argon broadened profiles of two ytterbium lines which form a stepwise e
xcitation route 6(1)S(0)-6(3)P(1)-7(3)S(1) are reported. The red and blue f
ar wing features are discussed and qualitative information on the argon-ytt
erbium potentials are obtained. It is shown that the system is suitable for
a two-step redistribution experiment.