Harry Kane gave the visitors the perfect start at the King Power Stadium, firing home his 13th goal of the season from Nacer Chadli???s cross to give Spurs the lead after just a minute.
However, Leicester fought back well and had their reward just after the break after Leonardo Ulloa tapped home Mahrez???s cross just after the break for his seventh goal of the campaign.
The momentum was with the home side but they could not take advantage and it was Eriksen who made them pay, beating Ben Hamer at his near post from a free-kick.
Leicester finished strong as they went in search of an equaliser and they thought they could have had a penalty when Jamie Vardy was brought down by Jan Vertonghen, but it was Spurs who nervously held on for a 2-1 win to take all three points back to north London.
Nigel Pearson made two changes for the home side with Ulloa and David Nugent coming into the attack but it was Spurs who showed their own cutting edge as they broke for the first time through Erik lamella.
The 22-year-old released Nacer Chadli down the left into space and he picked out a cross as Harry Kane nipped ahead of Leicester captain Wes Morgan, before firing past Hamer into the bottom right hand corner to give the visitors a flying start.
Despite being a goal down Nigel Pearson???s side were enjoying plenty of possession but as has been their problem for most of the season, they were not creating enough to trouble Hugo Lloris.
The Frenchman was finally called into action in the 18th minute as Ulloa flicked up the ball and fired a volley goalwards from outside the box which Lloris comfortable tipped over the bar.
However, it was Spurs who looked the more likely every time they moved forward and next it was Chadli who tested the keeper. Hamer could only parry the curling shot to Christian Eriksen inside the box, ??but the Dane???s shot was well blocked.
It was all becoming too easy for Spurs but with half-time approaching the home side, spurred on by their fans, came to life and should have scored the equaliser.
Excellent work by Drinkwater found Ulloa on the edge of the Spurs penalty area. The Argentine striker skipped past Danny Rose???s challenge and with the goal gaping missed his kick and the ball trickled out for a goal kick.
Momentum was certainly now with Leicester as Mahrez forced Lloris into a smart save but it was Ulloa who had Leicester???s best chance in the 39th minute.
Mahrez was the provider this time and placed a brilliant cross right on Ulloa???s head but with most of the goal to aim at the former Brighton striker could only hit the right hand post.
Despite Leicester???s excellent spell, Tottenham should have been out of sight just before the break as Kane rose highest to meet Lamela???s free-kick, but the England U21 international???s header flew wide with the goal at his mercy.
Pearson would have been delighted with how his side finished the first-half and despite replacing Andy King with Matty James due to injury, he would have wanted more of the same from his side.
In contrast, Pochettino would not have been pleased with what he saw towards the end of the first 45 minutes and attempted to shore up his midfield by bring on Ryan Mason for Stambouli.
However, the move did not work as Leicester responded straight away after more good work from Mahrez. ??The Algerian international broke free down the right and produced a low cross along the edge of the six yard box. Ulloa used his strength to get in front of Fazio and was on hand to level the scores from close range.
Leicester were now looking the more likely and minutes later they were denied the lead by the woodwork. The impressive Mahrez beat Lloris all ends up with his stunning free-kick but the ball cannoned back off the cross bar.
There was nothing coming from Spurs as an attacking force and Pochettino reacted by throwing on Roberto Soldado to partner Kane, however, it was Leicester on the front foot again.
This time it was Jeff Schlupp going close and it took a fine fingertip save from Lloris to push his thunderbolt shot around the post.
As with many of Spurs??? recent away performances there only looked like one winner and it was the home side. But with against the run of play, Kane won a free-kick to the left of the Leicester penalty area.
With just 20 minutes remaining, Eriksen seemed to be lining up to put in a cross but the Denmark international whipped in a free-kick which beat Hamer, who should have done better, at his near post.
The goal sucked the life out of Leicester and Pearson responded by sending Vardy on with 15 minutes remaining and it nearly had the desired effect as Jan Vertonghen appeared to bring the forward down in the penalty area.
There was no question the Belgium defender got a touch on the ball and there was more contact with the man, but referee Neil Swarbrick waved away the appeal.
Their final chance came as the impressive Mahrez sent in another testing cross which Lloris was forced to deal with. The ball fell at the feet of captain Morgan, but with the goal at his mercy he could not make proper contact and the ball was cleared to safety by Spurs.
The win means Spurs close the the gap to fourth place to just two points but despite another good Leicester performance, they stay rooted to the bottom of the table.