In the summer of 1995, De Boeck was transferred from KV Mechelen to Anderlecht. In the late 1990s, he was criticized by pundits, who claimed he was not good enough for Anderlecht. He eventually increased his technical performances to become one of the best defenders in The Jupiler Pro League in the early 2000s. In February 2005, De Boeck decided to end his career due to a heavy knee injury. He made a successful move to coaching to finally become Managing Director of Herculean, the corporate wellbeing company.
Coaching career
He was directly snapped up by his last club to become an assistant manager, together with Daniel Renders. On 23 April 2007, it was revealed that De Boeck would become manager of first division side Cercle Brugge at the end of the 2006–07 season. He succeeded Harm Van Veldhoven, who had already chosen to leave for Germinal Beerschot. On 1 February 2008, the board of directors at Cercle declared De Boeck had signed a new contract until 2011, as he also became the football section's technical director, being made responsible for the further development of the football team. In March 2009, De Boeck denied K.R.C. Genk in signing him as their new coach. Instead he choose to stay with his current club Cercle Brugge. He left Cercle in June 2010 and was named the manager of Germinal Beerschot who were looking for a successor to Jos Daerden who left to become an assistant coach at Dutch club Twente. On 30 November 2010, after continuous bad results and disagreements on the management board, he was fired as coach from Germinal Beerschot. At the start of the season 2011–2012 De Boeck was appointed as the new manager of VVV-Venlo, but halfway through the season on 6 December 2011, following a 7-0 defeat to Heracles Almelo, he resigned as manager of VVV-Venlo. In November 2012 he signed for Waasland-Beveren, but was released one year later. In January 2015 he started a new challenge in the business world as Managing Director for , the corporate wellbeing company.
International
De Boeck made his international debut with Belgium on 6 October 1993, against Gabon, going on to represent his country at two World Cups, with three appearances combined.