The other, shows Rocky, also with his back to the viewer, celebrating atop the Philidelphia Museum of Art.
There are a couple of different posters that are much better known when it comes to the original Rocky.
The decision was made to show less of the actual film in the poster, which was probably the right movie, as the best posters usually tease the film rather than reveal it.
Both are black and white, one shows Rocky and Adrien together with their backs to the viewer.