Leaders Leicester City belatedly grasped their golden opportunity to pile the pressure on their Premier League pursuers as a late strike from Leonardo Ulloa sank struggling Norwich City 1-0.
With closest challengers Tottenham Hotspur and Arsenal not in action until tomorrow, Leicester had the stage to themselves to forge five points clear at the summit and made the most of their chance with a victory they scarcely deserved.
Even though the team produced one of the least convincing displays of their surreal season, Ulloa's 89th-minute contribution, sliding in to knock home Marc Albrighton's cross, proved decisive for them.
It stretched Leicester's advantage significantly over the north London duo although both second-placed Spurs, at home to Swansea City, and Arsenal, who visit Manchester United, can reduce the deficit to two points again on Monday.
More importantly, it demonstrated to manager Claudio Ranieri that, following the heartbreak of the stoppage-time loss to Arsenal -- a defeat his men had two weeks to stew over -- they are not going to be easily deflected from their title ambitions.
"We believed until the end," the Italian told the BBC. "This victory was very important to restart after the Arsenal defeat.
"I said before the Arsenal match that Norwich would be more difficult. The conclusion I have drawn from this is that my players believe until the end. For us, the next match is always the final match. That is our mentality."
Chelsea also provided a rare reminder of their champions' mettle, fighting back from a goal down to take an excellent 2-1 win at Southampton, with an 89th-minute booming header from Branislav Ivanovic earning the spoils.
With Chelsea's Guus Hiddink and his former PSV Eindhoven player Ronald Koeman now doing battle as managers, it appeared the pupil might come out on top when Southampton took the lead through a Shane Long header just before the break.
Yet the visitors equalised through Cesc Fabregas in the second half, a goal which Koeman felt was lucky as his side had been deprived of what should have been a free kick moments before.
Afterwards, Hiddink, delighted that Chelsea had moved into 11th place under his soothing stewardship, reported that he was in no hurry to bring captain John Terry back into action after his recent hamstring injury.
"I hope that John is close to returning but we have a lot of games remaining. I don't want to take a big risk on his fitness," Hiddink told the BBC.
At the bottom of the table, Aston Villa's mission looked ever more impossible, with them still seven points adrift of the pack after a Marko Arnautovic double in the space of five minutes just after halftime helped Stoke City to beat them 2-1 at the Britannia Stadium.
In the day's early game, West Ham United surged into fifth place in the table in what has become their best-ever Premier League campaign in their final season at Upton Park, holding off a stirring fightback from Sunderland to win 1-0.
A fine curling shot on the half hour from winger Michail Antonio, courtesy of some poor defending from Patrick van Aaanholt, sealed the points.
Yet for Sunderland boss Sam Allardyce, back at his former club, there was nothing but frustration as his side squandered chances to still lie 19th, a point behind Newcastle United and Norwich.
Bournemouth earned a valuable point in their relegation fight, a goalless draw at Watford taking them to 29 points in 15th place, five clear of the drop zone, even though manager Eddie Howe felt they had played well enough to earn the win.
The day's late game witnessed spectacular fare at the Hawthorns as West Bromwich Albion opened a three-goal lead over Crystal Palace by halftime, including a first since October for Saido Berahino, only to eventually be left clinging on to a 3-2 win after a second half double from Connor Wickham.