More trouble for NFL player Mark Walton ... the running back was arrested AGAIN Thursday after cops say he was involved in a dispute with the mother of his child.
Police in Opa-Locka, Fla., tell CBS Miami ... they responded to a domestic dispute call around 3:30 a.m. and found 22-year-old Walton arguing with a woman.
After cops say they found the woman had a protection order against Walton ... they arrested the former Miami Dolphins player -- booking him at Miami-Dade County jail.
You can see in his mugshot, obtained by TMZ Sports, the dude was NOT pleased to be back behind bars.