Rocky III

During Rocky III's intro, Rocky is shown easily defeating numerous contenders in a montage, during which Lang is shown annoyed at Rocky apparently coasting through his title defenses. Lang decides to begin training himself to challenge Rocky and his methods bring results as he puts together a string of knockouts that soon make him the number one contender. Lang attends a charity exhibition match between Rocky and the professional wrestler, Thunderlips, but gets up and leaves in disgust shortly before the match ends. He appears at a public event to goad a now complacent Rocky who is announcing his retirement. Lang finally infuriates Rocky by propositioning his wife Adrian in front of Rocky's numerous fans and the television media, and Rocky agrees to fight him.

Rocky expects another easy victory and continues his complacent attitude towards training, which angers and worries his manager and trainer Mickey Goldmill. Meanwhile, Lang makes no such assumptions and relentlessly trains with fiercely disciplined intensity for the bout. On the night of the fight, Lang taunts the champion in the hallway as they are walking to the ring and provokes a scuffle between the two camps, shoving Mickey so hard that the latter suffers a heart attack which further distracts Rocky from the fight (and later proves fatal). He also angers former champion Apollo Creed by refusing to shake his hand before the fight and mocking him as a "has-been". Creed tells Balboa, "Give everybody a present and drop this chump." Lang overwhelms Rocky and knocks him out in two rounds.

Lang's first defense of his newly won title is a rematch against Rocky. Before the fight, Lang is interviewed and mocks Balboa as no challenge. When he is informed Creed is training Balboa and will be in his corner, Lang mocks Creed and says it does not matter. Balboa has learned a newer boxing style based on speed and finesse from Creed. Shortly before the fight, Lang mocks Creed again and even shoves him, nearly starting a brawl. The champion has trouble with Rocky's new technique and soon tires after becoming enraged and throwing a large number of wild hooks, attempting to knock Rocky out quickly. Although several punches are damaging, Balboa taunts Lang by saying "knock me out, champ" and claiming the resulting punches were "nothing", further enraging Lang who continues to swing wildly. Rocky exploits his opponent's exhaustion and knocks him out in the third round.^[6]

Lang's career results following the second fight with Balboa are unknown; outside of a replay of the final round in the beginning of Rocky IV, he was not seen in any of the Rocky or Creed films that followed. In one version of the script of Rocky Balboa, Lang became a born-again Christian and was now addressed by his given name of James. Lang was also slated to be one of the commentators of the Balboa vs. Mason "The Line" Dixon fight..