Mourinho has been brought in to take over from Mauricio Pochettino at White Hart Lane after the Argentine head coach was sacked by the Lilywhites on Tuesday night.
Spurs have struggled to find consistent form in the Premier League this season and they have only won three of their opening 12 games in the top flight under Pochettino.
Mourinho has been out of work since having been sacked by Manchester United last December and the Portuguese head coach will be eager to help try and turn around Spurs’ ailing fortunes.
England legend Shearer has admitted that he was surprised by the sacking of Pochettino and has warned Mourinho that he has a lot of work to do at the club.
Speaking to BBC Breakfast on Wednesday morning, Shearer said: “They say nothing should surprise you in football but it has moved really quickly.
“I was surprised by Pochettino’s sacking, you would think what he has achieved in the five years – turning them into regular top-four contenders and visitors to the knock-out stages of the Champions League – that he would have something in the bank, that he would be given a few months to turn things around.
“Mourinho has been waiting for a big job and now has got one. He has big boots to fill to try and better what Pochettino has done.
“The Argentine may not have won a trophy by the way that Pochettino delivered his football and that Champions League final was very special and will live with Spurs fans for many years.”
Tottenham will return to Premier League action on Saturday lunchtime when they take on West Ham United at the London Stadium.
They will then be back in Champions League action on Tuesday night when they take on Greek side Olympiakos.
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