Stegeman, 50, joined Willem II prior to the 2025-26 season and led the Tilburg side back to the Eredivisie after beating FC Volendam on penalties in the promotion play-off final.
The return to the Eredivisie hasn't gone as planned for Willem II, who have gone winless through the first nine rounds and picked up just two points. The Tricolores sit bottom of the table with the league's worst defensive record, having conceded 26 goals.
Stegeman's dismissal was Willem II's fifth managerial sacking in five years.
"Following promotion to the Eredivisie, our ambition was to continue working with John to further develop Willem II’s sporting programme. That is why this has been a difficult decision," technical director Freek Heerkens said on the club website.
"Following a careful review and discussions amongst ourselves, we do not currently see sufficient prospects for continuing our collaboration. We would like to thank John for his dedication, the pleasant working relationship and his commitment to the club."
Assistant managers Danny Schenkel and Pim Hendrix will temporarily take over from Stegeman.
Willem II face fellow promoted side Cambuur Leeuwarden next on Saturday, October 24th, before visiting Helmond Sport in the KNVB Beker next week.
Flashscore covers the 2026/27 Eredivisie season week in, week out, with match reports and daily roundups. From PSV's title defence to Telstar's relegation fight and Ajax's resurrection.
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