The north London side decided to make a change eight days into the international break after Spurs drew 1-1 with Sheffield United at the Tottenham Hotspur Stadium last time out.
Mourinho was officially confirmed as Spurs’ new manager on Wednesday morning soon after the Lilywhites announced the departure of Pochettino on Tuesday night.
The Lilywhites have made a poor start to the Premier League season as key players such as Harry Kane, Christian Eriksen, Dele Alli and Hugo Lloris struggle to find form.
Tottenham are in 14th position in the Premier League table and 11 points behind defending champions Manchester City, who occupy the final Champions League qualification spot.
Spurs reached their first-ever Champions League final last season before the north London outfit suffered a 2-0 loss to domestic rivals Liverpool FC in the final.
Pochettino steered Tottenham to a top-four finish in their last four seasons under the former Southampton boss.
Tweeting before Mourinho’s appointment on Wednesday morning, former Spurs striker Lineker had his say on the north London club’s decision to sack Pochettino.
Lineker wrote on Twitter: “Mauricio Pochettino has been sacked by
@SpursOfficial. He helped the club to punch massively above their weight for years. Good luck with finding a better replacement….ain’t gonna happen.”
Tottenham have never won the Premier League title despite challenging for the top-flight crown twice under Pochettino.
Spurs will return to Premier League action with a trip to bitter London rivals West Ham United at the London Stadium on Saturday.
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