Danny Ings continued his golden run of form as Southampton enjoyed a 1-0 victory against Tottenham, whose miserable afternoon was made worse by an injury to Harry Kane.
Ings fooled former Southampton defender Toby Alderweireld with a great piece of skill to fire the hosts in front in the 17th minute and a laboured Tottenham rarely threatened.
A hamstring injury to Harry Kane that forced the England striker off in the second half ensured it was a miserable start to the new year for Tottenham, whose manager Jose Mourinho was booked for an altercation with the home coaching staff.
Kane was injured scoring a goal that was disallowed for offside, the decision confirmed by VAR.
A third league defeat of Mourinho's reign leaves them six points adrift of Chelsea in fourth place and after an initial surge under the Portuguese, Spurs are back to playing the standard of football which cost Mauricio Pochettino his job.
Leicester City striker Ayoze Perez came back to haunt his former team Newcastle United with a goal and an assist for midfielder James Maddison, as the Foxes eased to a 3-0 victory and cut the gap to runaway Premier League leaders Liverpool.
The Foxes made light of Jamie Vardy's absence due to a calf injury as Perez pounced on a poor pass across the back line from Newcastle defender Florian Lejeune and rode a tackle from Fabian Schar before slotting past Martin Dubravka in the 36th minute.
Lejeune was in the spotlight for the wrong reasons again as his poor clearance found its way to Perez who fed Maddison, and the England international blasted in a left-footed shot from distance three minutes later.
The double blow came shortly after Newcastle had missed the chance to take the lead through Brazilian forward Joelinton, who sprinted onto a pass over the top of the Leicester defence but failed to beat goalkeeper Kasper Schmeichel with two attempts.
With Newcastle reduced to 10 men after using up their three substitutions and Schar unable to play due to injury, Leicester made it 3-0 in the 87th minute through Hamza Choudhury who curled in a shot from outside the penalty area.
Ten-man Watford continued their fine run of form under new manager Nigel Pearson and boosted their hopes of avoiding relegation from the Premier League with a 2-1 home win over Wolverhampton Wanderers.
Gerard Delofeu and Abdoulaye Doucoure fired Watford ahead before Pedro Neto pulled one back for Wolves, who failed to capitalise on a numerical advantage in the last 20 minutes after defender Christian Kabasele was sent off for the hosts.
Deulofeu opened the scoring with a neat 30th-minute finish when he beat goalkeeper Rui Patricio with a crisp low shot into the far corner after good work by Ismaila Sarr.
Doucoure made it 2-0 in the 49th when he cut inside from the left and found the top corner with a firm drive which clipped Wolves defender Conor Coady and left Patricio stranded.
Neto reduced the arrears on the hour with a heavily deflected effort which sailed over Ben Foster and Wolves piled the pressure after Kabasele was shown a straight red card following a VAR review.
The centre back was originally booked for hauling down Diogo Jota just outside the penalty area but Watford held on in the closing stages to celebrate their third league win coupled with one draw under Pearson