Spurs underlined their credentials as genuine Premier League title contenders this season when they thrashed Liverpool 4-1 at Wembley to stay on the coattails of Manchester City at the top of the table.
Mauricio Pochettino’s men are currently third and five points behind the Citizens after nine games of the new campaign.
Manchester United, meanwhile, are currently licking their wounds after the disappointment of their 2-1 loss to Huddersfield in the top flight on Saturday.
The Red Devils are currently second and also five points behind the leaders.
And former Manchester City boss Pearce reckons that the Premier League title race is shaping up as a three-team affair this season.
Speaking on Sky Sports News on Monday morning, Pearce said: “I think from a two-horse race it has become a three-horse race now, I really do.
“Tottenham look like the unstoppable side.
“The only thing that will curtail that is the odd injury somewhere.”
Manchester United will return to Premier League action on Saturday lunchtime with a crunch clash against Tottenham Hotspur at Old Trafford.
The Red Devils are aiming to win the title this season for the first time since Sir Alex Ferguson’s final campaign in charge in 2013.
Manchester United finished sixth and won the Europa League and League Cup last term.
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