French midfielder / striker Antoine Sibierski signed for Norwich City just shortly before the summer 2008 transfer window closed on 1st September 2008. This was the second time that Norwich manager Glenn Roeder had signed Sibierski on transfer deadline day.

Sibierski began his career at his hometown club Lille, where he progressed from the youth team and played for four complete seasons in the first team before playing for Auxerre (1996-98) and Nantes (1998-2000), where he won the French Cup in 2000. He then joined Lens (2000-03), and he became club captain within his three years in the side.

Sibierski moved to Manchester City for a fee of £700,000 in August 2003 and scored on his debut against Charlton Athletic. Over the next three seasons, he made 92 appearances for City, scoring 11 times

Roeder signed Sibierski for Newcastle on 31st August 2006 on a one-year contract, just two hours and twenty minutes before the close of the transfer window. He scored on his Newcastle debut in the UEFA cup first round tie against Levadia. His goal scoring form at the start of the season proved many Geordie doubters wrong, as Sibierski went on to be a key European figure as he made 7 European appearances and scored 4 essential goals. He quickly became a Newcastle favourite and an important member of the first team loved by the Newcastle faithful

However Newcastle were not willing to match Sibierski's wish of a new two-year contract at the club, instead offering just another one-year contract, which he rejected. Sibierski agreed a two-year deal with Wigan Athletic on a free transfer from Newcastle United on 4th June 2007. He scored on his Wigan debut in the 2-1 defeat at Everton on 11th August 2007. He suffered from injuries during 2008/8 and was limited to 30 appearances, scoring 4 goals.

Sibierski made his debut on 13th September 2008 in the 2-1 away win at Plymouth and scored Norwich's second goal.

Sibierski returned to Wigan on 12 January 2009 after injury was sustained in Norwich's 1-0 defeat to Sheffield United on 10th January 2009. He made 16 appearances for Norwich scoring twice.

Sibierski was released by new Wigan manager Roberto Martinez in the summer of 2009. He has since retired and became a football agent with his brother.

In the summer of 2012, Antoine was appointed sporting director at French Ligue 2 club RC Lens, whom he had previously played for.

In 2024 he resurfaced as a coach at third tier French side LB Chateauroux before being appointed as Sporting Director of Troyes in July 2024. Troyes are part of the City Football Group but were relegated to the third tier of French football at the end of the 2023/24 season.