João Pereira took over after successful coach Rúben Amorim, who on November 10 became coach for Premier League club Manchester United.
Since then, the reigning champion team Sporting Lissabon has struggled. The team suffered four consecutive losses between November 26 and December 10.
Although there have been two wins since then, the meeting with table-ten team Gil Vicente on Sunday ended 0–0, and the day after, rival Benfica could take over the league lead.
Now the club announces that Pereira is fired and replaced by Rui Borges, who is bought out from league competitor Vitoria Guimarães for approximately 47 million kronor (4.1 million euro).
Borges took over Vitoria Guimarães in May, which is sixth in the domestic league. The team is clear for the round of 16 in the Conference League after finishing second in the league phase behind Chelsea.
It has also been tough for Swedish national team star Viktor Gyökeres lately. The striker has "only" scored four goals in eight matches under Pereira.
On Sunday, an early season final awaits when table-two Sporting visits league-leader Benfica.
Corrected version: In an earlier version, incorrect goal statistics for Gyökeres in matches under Pereira were stated.
