Amakhosi, defending PSL champions, managed only their third win of the campaign on Saturday as they pipped last term's runners-up to the three points with a win at the FNB Stadium.
"We lacked professionalism. I have a gripe with my team for not taking our chances," Baxter told his club's official website.
"If you look at Stars, they scored a goal against the run of play, and started playing good football. Poor decision making nearly cost us a game.
"We dominated most of the game, but didn't use transition very well until we sneaked in two goals. We lacked discipline on set play. Though our movement was spot on for most of the game, we were inconsistent and not calm when in possession."