▁the ▁director ▁has ▁no ▁short age ▁of ▁famous ▁people ▁showing ▁up ▁— ▁Mark ▁Wahl berg , ▁Den zel ▁Washington , ▁Ron ▁Howard , ▁S pi ke ▁Lee , ▁Mary ▁J . ▁Bl ige , ▁ 5 0 ▁Cent ▁— ▁their ▁contributions ▁are ▁carefully ▁and ▁taste fully ▁selected , ▁with ▁Marcus ▁largely ▁c eding ▁to ▁the ▁more ▁knowledge able ▁and ▁less ▁flash y ▁exper ts , ▁who ▁are ▁the ▁ones ▁that ▁truly ▁contribute ▁the ▁context ▁to ▁make ▁Cham ps ▁as ▁insight ful ▁as ▁it ▁is ", ▁and ▁Z eb a ▁Bl ay ▁described ▁it ▁as ▁" more ▁a ▁social ▁document ary ▁than ▁a ▁sports ▁document ary ". ▁ ▁As ht on ▁Morris ▁of ▁The ▁Hot ▁Zone ▁said , ▁" B ert ▁Marcus , ▁with ▁keen ▁intellect ▁and ▁wh ims ical ▁cre ativity , ▁ill umin ates ▁a ▁long ▁ignored ▁" issue " ▁– ▁that ' s ▁putting ▁it ▁light ly ▁– ▁in ▁a ▁sport ▁that ▁has ▁left ▁its ▁mark ▁on ▁the ▁fabric ▁of ▁our ▁country ' s ▁history ." ▁ ▁Additionally , ▁various ▁inter views ▁with ▁cast ▁members ▁the ▁director ▁were ▁featured ▁during ▁the ▁film ' s ▁release , ▁explaining ▁that ▁this ▁film ▁is ▁more ▁than ▁just ▁a ▁box ing ▁film . ▁ ▁Se an ▁Cro se ▁of ▁Box ing ▁Ins ider ▁writes , ▁"[ p ] er haps ▁that ' s ▁why ▁Marcus ' ▁new ▁document ary , ▁Cham ps , ▁de als ▁with ▁more ▁than ▁just ▁its ▁main ▁subjects : ▁Mike ▁T ys on , ▁Ev ander ▁Holy field ▁and ▁Bernard ▁Hop