As an amateur boxer out of the famous Lynn AC boxing gym in SE London, Williams learned his trade quickly, often sparring with the likes of clubmates Henry Akinwande and Derek Angol.
Williams won the title with a closely contested split decision over respected British contender (and former amateur clubmate) Harry Senior.
[2] After an eight-month layoff for surgery and recovery, Williams returned to knock out a respected opponent – Kali Meehan in 32 seconds,[3] and then avenged his defeat to Francis, stopping him on an eye injury in the 4th round.
[5] His tenure under King would prove to be uneventful, and he did not renew his contract at the end of 2002, a year that saw Williams retain his British and Commonwealth titles with a knockout of late sub Michael Sprott[6] and a points win over Keith Long.
As this was Williams' third defence of the British title, he won the Lonsdale belt outright,[7] before dropping out of a fight in America with hard hitting South African southpaw Corrie Sanders, because it coincided with Ramadan.
[citation needed] In February 2003 Williams travelled to Germany to fight the Turk Sinan Samil Sam for his European heavyweight title.
To begin 2004, Williams re-signed with Frank Warren then lost his British and Commonwealth in a third meeting with Michael Sprott via a disputed close points decision.
After two comeback knockout wins, Williams boxed former world champion Mike Tyson in Freedom Hall State Fairground, Louisville, Kentucky in July 2004.
In December he finally challenged for a world heavyweight title, but Vitali Klitschko proved too much, as Williams was stopped in the 8th round.
[9] In December Williams regained his old Commonwealth belt by beating undefeated Olympic gold medallist Audley Harrison by split decision.
Williams retained the Commonwealth title with a controversial points win over undefeated Matt Skelton in March 2006.
The Ukrainian picked up a badly-bleeding cut above the left eye following an accidental headbutt in the second round and he continued to swing wild punches but not without taking some huge shots from Williams.
"[citation needed] On 30 May 2008 Williams defeated unbeaten German, Konstantin Airich in a highly controversial fight.
Williams had a total of 3 points deducted in rounds 2 and 5[10] creating a feeling afterwards that the referee was blatantly on the side of the German.
[citation needed] Williams suffered a shock defeat by 8th-round TKO and as a result the Botha fight was called off.
The McDermott rematch was finally arranged for 2 May 2009 in a defence of the British Heavyweight Championship belt that Williams held.
In his first bout on the night, Carl Baker from Sheffield beat Williams on points after knocking him down twice in the opening round.
[16] Williams returned to boxing after nearly a year of inactivity with a 2nd-round TKO victory over German Frank Kary Roth in Bielefeld on 5 March 2011.
A fight with unbeaten Alexander Ustinov was set to take place in October 2011, but Williams withdrew due to a viral infection.
[18] Williams fought the Norwegian heavyweight boxer Leif Olve Dolonen Larsen in Pabellon Municipal, Silla, Valencia, Comunidad Valenciana, Spain on Friday 2 December 2011.
Once again, Williams's retirement proved to be short-lived as he fought Denis Bakhtov in Podolsk, Russia on 8 December 2012, losing by unanimous decision over 10 rounds.
Williams claimed the lightly-regarded Global Boxing Federation (GBF) World Heavyweight title on 28 April 2018 in Hungary when he defeated Czech journeyman Martin Stensky.
In July 2018 in Aberdeen, Williams lost a WBU heavyweight title fight on an event sanctioned by the British & Irish Boxing Authority against former lightweight Lee McAllister.