Ehrhoff akakwikwidza nechikwata cheGermany chevadiki pasi pemakore gumi nemasere pamutambo wekutanga we1999 IIHF World U18 Championships, yakaitirwa muFüssen neKaufbeuren, Germany. Akadzoka gore rakatevera nokuda kwe2000 IIHF World U18 Championships muSwitzerland, uko Germany yakapedza panzvimbo yechinomwe. Ehrhoff akabva atanga pamutambo we under-20 muDivision I ye 2001 World Junior Championships
. Kugamuchira mutambo mumaguta eFüssen neLandsberg, Germany yakarasikirwa nekusimudzirwa kumakwikwi makuru gore rinotevera nekupedza munzvimbo yechipiri kuseri kweFrance. Ehrhoff akaita chitarisiko chake chechipiri paChikamu I pamutambo we2002 World Junior Championships muAustria, achitungamira vese vadziviriri vemutambo aine zvibodzwa zvitatu uye mapoinzi gumi mumitambo mishanu. Akabatsira Germany kuwana kukwidziridzwa kumutambo mukuru wegore rinotevera, achikunda Austria 7<unk>1 mumutambo wemenduru yegoridhe. Mumakore ose ari maviri achikwikwidza mumutambo, Ehrhoff akawana rukudzo rweTop Defenceman.