U qor sii wadida cutubkan - Lehmann wuxuu u ciyaaray AIK horyaalka Elitserien ee Sweden shan xilli ciyaareed laga bilaabo 1982 ilaa 1987. Waxaa doortay Boston Bruins ee National Hockey League ee 1982 NHL Entry Draft
, wuxuu ku biiray Boston xilli ciyaareedkii 1987/88, wuxuuna ciyaaray sagaal kulan xilli ciyaareedkaas, iyo 26 kulan oo dheeri ah xilli ciyaareedkii xigay, isagoo ku qaatay inta badan labadii sano ee uu u ciyaaray kooxda Bruins 'American Hockey League ee Maine Mariners. Waxaa loo beddelay Edmonton Oilers ka hor xilli ciyaareedkii 1989-90, laakiin wuxuu u ciyaaray hal ciyaar oo kaliya kooxda. Lehmann wuxuu u ciyaaray 19 ciyaarood oo caadi ah iyo 6 ciyaarood oo playoff ah oo loogu talagalay Cape Breton Oilers ka hor inta uusan ku laaban Sweden. Lehmann wuxuu ciyaaray toddobo sano oo kale Elitserien, inta badan AIK, laakiin sidoo kale MODO hal xilli ciyaareed, iyo hal ciyaar oo Södertälje ah xilli ciyaareedkiisii ugu dambeeyay, ka hor inta uusan fariisan 1997.