A graduate of Princeton University,[2] Wallace began his pro career in Germany, and he played with the Eisbären Bremerhaven for two years, before moving to Orlandina Basket (Capo D' Orlando) in the Italian first league. During the 2007–08 season, Wallace led the Italian league in rebounding, at a nearly 10.8 boards per game average, while also scoring 14.4 points a game, and shooting nearly 38% from three-point range.[3] Along with Italian legend Gianmarco Pozzecco, and the other Orlandina players, the Capo D' Orlando team finished in the sixth position, in its first-ever trip to the Italian league playoffs, where they eventually lost to Air Avellino.
On September 7, 2011, Wallace signed a two-year deal with the Spanish powerhouse FC Barcelona.[5]
On August 6, 2013, Wallace signed a two-year deal with Italian club Emporio Armani Milano.[6] In July 2014, he was released from Milano, along with Gani Lawal.[7]
On November 20, 2014, Wallace signed a one-month deal with Élan Chalon of the French LNB Pro A.[8] On January 5, 2015, he signed with French club Le Mans Sarthe Basket, for the rest of the season.[9]