Buchanan started his professional career in 2004 and got off to an amazing start scoring 10 straight stoppage wins in just 14 months. He was touted by some as an excellent prospect and by October 2006 he had advanced his record to 14-0 (11) with the idea that he was going to be moved into title contention sooner rather than later. The brakes were put on his career soon afterwards as Frenchman Jean-Paul Mendy scored a wide unanimous decision over "Sugar Poo".
Following the loss to Mendy Buchanan would take a year out of the ring before returning to action and defeating Ted Muller over 8 rounds and followed it up with 2 more wins before facing his most well known opponent to date, Andre Ward. Ward would dominate Buchanan over 12 rounds and take a complete shut out as he progressed his own career the heady heights that he has now reached.
Over the following 18 months Buchanan tried to rebuild his career and scored 3 more victories including one over respectable journeyman Julius Fogle (who was then 15-2-0-1 (10), though is now 15-7-0-1 (10)). He was then supposed to face former Light Middleweight champion Fernando Vargas (who was ending a 4 year retirement) but that bout was cancelled and Buchanan would actually be out of the ring until earlier this year. On his return to the ring, Buchanan, who had been away from the ring for over 20 months was out pointed by Shawn Hawk.
At 33 years old we may well see "Sugar Poo" in the ring once again, though it's fair to say he no longer has the career momentum that he once had and may well be better off watching his nephew, NFL star Shawne Merriman. In terms of Nicknames Merriman certainly has the better on as he known as "Light Out" a nickname he shares with boxing great James Toney.