Waasland-Beveren would eventually face the same fate as a few weeks later they lost the Relegation play-off against Seraing, ending a span of nearly a decade at the top level.
The bigger clubs agreed to continue the current format but demanded that U23 teams be permanently added to the lower leagues.
[1] Returning to top-flight football after 48 years away, Union Saint-Gilloise earned a 3–1 opening-day win away to Brussels' traditional giants Anderlecht,[2] Union hosted reigning champions Club Brugge on 1 August 2021 in their first home game in the top division since 1973, being edged out 1–0 through a late Eduard Sobol winner.
In a difficult January run against all of the previous season's top four, Union beat Anderlecht, Genk and Royal Antwerp, drawing 0–0 away to Club Brugge.
[2] Union started the play-offs strongly, beating Anderlecht 3–1 and thus becoming the first club ever to inflict three defeats on the Mauves in the same league season.
Club Brugge won the midweek return 1–0 at the Jan Breydel through an own goal from goalkeeper Anthony Moris to take a three-point lead with two games to go.
[4][5] Club Brugge clinched the league crown in their next (and penultimate) game against Royal Antwerp,[6][7] despite Union beating Anderlecht for the fourth time in the season 2–0 at Lotto Park.
It was the completion of a three-in-a-row for Club Brugge, whose coach Alfred Schreuder would leave within 48 hours of the title success for Ajax.
One day later in the 2021–22 Belgian First Division B, RWDM lost their match away to Deinze, meaning they would finish second and thus play Seraing for promotion.