Go to the Skum Pitt in Junktown in the evening and wait for a while. Soon you will witness one of the Skulz assault Trish, the barmaid. She will scream for Saul to help her, but Neal blows the Skulz ganger away. (The ganger will have a Knife and leather armor).
The player should then question Trish about why she screamed out Saul's name; she will explain that he is her boyfriend, and an excellent fighter. She also says that he hangs out at the boxing ring during the day.
The next morning, the player needs to go and see Saul at the boxing ring, to talk to him until the topic of Trish comes up. The player should inform him that she is concerned about his well-being. He will thank you and promise to talk with her.
Finally, the player should talk with Trish again and explain to her that she can't change her man, and must take him as he is.