Lanús remained in Primera until 1949 when the team was relegated after a controversial decision from the Association. At the end of the tournament, Boca Juniors was placed last and Lanús penultimate. On 8 December Boca smashed Lanús by 5–1, which finished last along with Huracán. In order to define which team would be relegated, Lanús and Huracán had to play a relegation series. Huracán won the first game 1–0 and Lanús took revenge by 4–1 in the second match so a third game was played. With a partial score of 3–3 the referee awarded a penalty kick to Lanús. The Huracán players, in disagreement with the decision, abandoned the field being the match suspended. The Argentine Association not only did not punished Huracán but it decided to play a new match. During that fourth game the referee did not award a penalty kick to Lanús while Huracán was winning the match by 3–2. As a result, the Lanús players left the field (as their rivals had done before). But the Association decided to punish Lanús relegating the club to Primera B.