The injury outlook didn't get any brighter for the Pistons after Tuesday's practice.
  Jerry Stackhouse, whose strained left groin improved enough to allow him to participate in some drills, is still unlikely to play Thursday against the Knicks.
  And Dana Barros, who returned last Sunday after missing four games, appeared to reinjure his left hamstring.
  "Dana tweaked his hamstring during practice and went out early," Coach Rick Carlisle said. "I don't know how badly he reinjured it, but it appeared he did something to it again."
  The team's official medical report called it a hamstring strain. Barros underwent additional tests Tuesday afternoon and will undergo more treatment today.