The Sportsmaster is a villain who used his sports skills for criminal purposes. Sportsmaster was one of the participants at Roulette's Metabrawl. He later joined Grodd's Legion of Doom.
Sportsmaster first appears in the Justice League Unlimited episode "The Cat and the Canary". When Black Canary waited for Wildcat to show up to help her take on some criminals, she finally called him. Wildcat answered that he got hung up, as he was busy fighting Sportsmaster. Sportsmaster then used this chance to punch Wildcat in the jaw, forcing him back. Dodging another one of Sportsmaster's blows which barely missed his jaw, Wildcat refused help from Black Canary. Sportsmaster swung again at that moment, but Wildcat blocked, fended him off, then boxed him squarely in the face, knocking him backwards. Sportsmaster regained his balance and swung again, but Wildcat ducked, defeating Sportsmaster with a punch into the villain's stomach. Sportsmaster was also a frequent fighter in Roulette's on again/off again Meta Brawl's. Later, he joined the Legion of Doom, as he can be seen sitting at the Legion's table during later episodes.
Because of the Bat-Embargo to limit or ban the use of Batman related characters from any media source outside of the Batman Begins movie franchise and The Batman animated series meant that only more obscure Bat-villains such as the KGBeast, Clock King, Gork, Sportsmaster, Blockbuster or Copperhead would appear in the DCAU.