▁Copa ▁de ▁Honor ▁C ous en ier ▁( 1 9 0 7 ). ▁ ▁Bel gr ano ▁Athlet ic ▁played ▁one ▁of ▁the ▁earliest ▁football ▁rival ries ▁against ▁Bel gr ano ▁neighb ours ▁Al umn i , ▁the ▁most ▁successful ▁team ▁of ▁Argent ine ▁until ▁its ▁dissol ution ▁in ▁ 1 9 1 1 . ▁Both ▁teams ▁were ▁so ▁strong ▁that ▁they ▁won ▁all ▁of ▁the ▁th ir teen ▁league ▁titles ▁cont ested ▁between ▁ 1 8 9 9 ▁and ▁ 1 9 1 1 ▁( that ▁was ▁the ▁last ▁year ▁of ▁Al umn i ▁football ▁team ▁compet ing ▁in ▁Argent ine ▁league , ▁being ▁officially ▁dissol ved ▁in ▁ 1 9 1 3 ). ▁ ▁Bel gr ano ▁AC ▁would ▁achieve ▁a ▁historic ▁victory ▁over ▁River ▁Pl ate , ▁defe ating ▁the ▁Mill on ario ▁ 1 0 – 1 ▁in ▁ 1 9 1 2 . ▁That ▁was ▁the ▁worst ▁defeat ▁of ▁River ▁Pl ate ▁in ▁club ' s ▁history . ▁ ▁Despite ▁of ▁being ▁one ▁of ▁the ▁most ▁notable ▁football ▁teams ▁during ▁the ▁first ▁years ▁of ▁that ▁sport ▁in ▁Argentina , ▁Bel gr ano ▁was ▁re leg ated ▁from ▁the ▁Argent ine ▁Primera ▁División , ▁along ▁with ▁Qu il mes ▁in ▁ 1 9 1 6 . ▁ ▁Bel gr ano ▁never ▁returned ▁to ▁the ▁first ▁division , ▁and ▁the ▁club ▁later ▁dis aff ili ated ▁from ▁the ▁Argent ine ▁Association , ▁foc using ▁on ▁the ▁pract ise ▁of ▁other ▁sports , ▁mainly ▁rugby ▁union . ▁ ▁Rugby ▁union ▁