Liverpool loanee Fabio Borini boosted his parent club's Premier League title bid as Sunderland claimed a shock 2-1 win at Chelsea.
Borini, who was once on the books at Stamford Bridge, converted an 82nd-minute penalty after Cesar Azpilicueta had fouled substitute Jozy Altidore to end Jose Mourinho's 77-match unbeaten run in home league encounters as Chelsea boss.
It is the second time this week that Sunderland have bolstered Liverpool's cause following the 2-2 midweek draw with third-placed Manchester City.
And the result simultaneously provided a huge lift to the survival chances of Gus Poyet's side, who are now only three points from safety.
Having scored a brace in Wednesday's encounter at the Etihad Stadium, Connor Wickham struck in the 18th minute to cancel out a Samuel Eto'o opener for Chelsea.
An error from Vito Mannone had handed City a point but Chelsea found Sunderland's goalkeeper in superb form as he produced an inspired string of saves before half-time.
Eto'o and substitute Demba Ba spurned chances in the second period before Borini struck - meaning that Liverpool can now open up a five-point cushion ahead of the top two's crunch meeting at Anfield next week if they beat Norwich City in Sunday's early kick-off.
Chelsea went into the match boasting nine consecutive home clean sheets - a record that 41-year-old goalkeeper Mark Schwarzer had to protect on his Premier League debut, with Petr Cech laid low by a virus.
The veteran Australian watched Borini fire a seventh-minute drive wide following some impressive hold-up play from Wickham.
Eto'o was then denied by a perfectly timed sliding tackle from Santiago Vergini but responded to volley home the resulting 12th-minute corner.
The lead was soon wiped out, though, when Schwarzer spilled Marcos Alonso's dipping drive and Wickham reacted quicker than John Terry to convert the rebound.
Slack set-piece marking almost undermined Sunderland again in the 37th minute but Mannone grasped Branislav Ivanovic's header at the second attempt via the crossbar.
There was little let up for the Italian goalkeeper as half-time approached and he produced impressive saves to thwart Willian and Nemanja Matic from close quarters.
In the 44th minute, after Mannone had parried from Willian, Sebastian Larsson out-muscled Ramires as the Brazilian looked to convert into an empty net.
Perhaps still suffering the frustration of that incident, Ramires was then fortunate to escape punishment when he struck Larsson with his elbow.
A breathless opening period concluded when Chelsea defender Azpilicueta made a last-ditch challenge to deny Adam Johnson having conceded possession to the Sunderland winger.
Chances continued to flow for Chelsea and Eto'o guided the ball wide after Willian had driven forward on the counter-attack in the 48th minute.
Mourinho sent on Ba in place of the ineffective Oscar but the player who netted vital goals in the recent triumphs over Paris Saint-Germain and Swansea City found the Midas touch had deserted him, losing his footing when trying to get on the end of Willian's 66th-minute cutback with the goal gaping.
Sunderland weathered further pressure before Azpilicueta clumsily bundled Altidore to the floor and Borini stole the points from the spot with eight minutes left.
Poyet's team remain bottom of the table but three of their four remaining games are at home against fellow strugglers Cardiff City, West Brom and Swansea City.
|Coach: José Mourinho|
for Oscar 59'
for Mohamed Salah 66'
for S. Eto'o 74'
|Ronaldo reiterates desire for Zidane to continue as Madrid coach|
|Keane: City need to improve to win Champions League|
|Falcao left out of Colombia´s Copa America squad|
|Carragher: Sturridge must start against Villarreal|
|De La Hoya´s clanger: ´Whoever thought Leicester would win the UEFA Cup?´|
|Marotta: City asked, but it´s not time to sell Pogba|
|Marcelino wants to turn Anfield atmosphere in Villarreal´s favour|
|Marcelo calls for La Liga focus after Madrid reach Champions League final|
|Origi hopeful of returning before season´s end|
|Madrid were the better side, insists Ronaldo|
|Mangala: City should be proud of semi-final run|
|Madrid move motivated by Champions League glory, says Bale|
|We will leave our soul in the final - Ramos|
|Hart left broken by ´very lucky´ Madrid goal|
|Zidane hails victorious Madrid|
|Pellegrini disappointed to miss out in tie of few chances|
|Real Madrid 1 Manchester City 0 (1-0 agg): Zidane´s men set up 2014 final repeat|
|Lucescu: Shakhtar ready for hardest fight|
|´Benteke cost almost Villarreal´s budget!´ - Marcelino expects major Liverpool test|
|AFC Champions League Review: Big-spending Jiangsu Suning dumped out|
|Kompany off injured in Champions League semi|
|Ter Stegen: I want to stay at Barcelona|
|Vardy will thrive for England at Euro 2016, says Smith|
|Lemina eyes key role at Juventus|
|Cerezo hits back at Vidal´s ´ugly´ swipe|
|Bacca happy at Milan without European football, says agent|
|Long backs Saints to end Spurs hoodoo|
|West Ham´s Sullivan labels Leicester lucky|
|Alba admires Atletico team work|
|Ranieri deserves an honour - Italian prime minister|
|Klopp bullish ahead of semi-final showdown|
|Ranieri´s 96-year-old mother: Now my son is King of England|
|Lovren: Europa League final would save Liverpool´s season|
|BREAKING NEWS: Dembele set for long FA ban over Costa altercation|
|AC Milan ultras call for Galliani´s head over ´blatant mockery´ of fans|
|Emery wants ´inspired´ Konoplyanka in Europa League semi-final|
|Wendell Lira blames Puskas Award trip for club woes|
|Joe Cole in line for Tampa Bay Rowdies move|
|Fuchs: I could kiss Hazard after title-clinching goal|
|Hiddink turned down Leicester before Ranieri appointment|
|Arsenal did not hold their nerve in title race - Smith|
|Cazorla targets City comeback for Arsenal|
|Webb could face lifelong ban as FIFA opens proceedings|
|Smith backs Leicester to become Premier League ´force´|
|Toni to retire after Juventus clash|
|Iwobi reveals key to dream Arsenal rise|
|Allen expects to reach Europa League final|
|McLeish leaves Zamalek after 65 days|
|Football fans pile bets on Burnley to win Premier League after Leicester´s shock success|
|Ranieri: Rich teams will win for next 10 to 20 years|
|Pity we could not reward Guardiola for his three years, says Bayern captain Lahm|
|Madrid revenge no factor for Simeone|
|Copa Libertadores Review: Pumas UNAM, Atletico Nacional advance to quarter-finals|
|Adelaide want Leicester City friendly|
|Tottenham have proven critics wrong - Eriksen|
|Ferdinand ´turned on´ by Simeone´s Atletico|
|Wilson hoping Brighton experience enough for United|
|Griezmann urges team-mates to keep feet on the ground|
|We´ve learned from past errors - Fernandinho|
|Payet cleans up West Ham awards|
|´We don´t need superstars´ - Ranieri|
|Vidal: Bayern are still the best in the world|
|Guardiola: I have given my life to Bayern|
|Simeone: Atletico have eliminated two of the world´s three best teams|
|Leicester owner reveals Vardy signing doubts|
|Bayern feel cheated, says Rummenigge|
|Boateng: Bayern solely to blame for Champions League exit|
|Zabaleta confirms calf injury|
|´It was a siege´ - Torres proud of Atletico after holding off Bayern|
|Liverpool v Villarreal: Klopp demands improvement in Anfield return|
|Bayern Munich 2 Atletico Madrid 1 (2-2 agg): Griezmann clinches final berth with away goal|
|AFC Champions League Review: Victory, Al Hilal and Al Ain qualify with wins|
|Courtois ´100 per cent´ committed to Chelsea, denies PSG contact|
|Pellegrini: Madrid are more than Ronaldo|
|Trabzonspor handed four-game stadium ban|
|Morata muscle tear ruled out|
|Sevilla v Shakhtar Donetsk: Vitolo fired up to seal historic Europa League final spot|
|UEFA has opened Pandora´s box with Kosovo decision - Serbian FA president|
|Infantino claims positive response to FIFA funds plan|
|Aubameyang reiterates Real Madrid desire|
|Huth and Fellaini charged by FA|
|Cahill hopes for FA understanding after fiery Tottenham clash|
|Kehl slams Dortmund fans over Hummels boos|
|Mourinho congratulates Ranieri for winning ´my title´ with Leicester|
|Confusion reigns as City confirm Toure travels to Madrid|
|Mata: United can finish fourth and win FA Cup|
|Missing Champions League final would be a failure - Zidane|
|City without Toure for Real Madrid semi-final|
|Infantino hails Leicester title as ´the magic of football´|
|Redknapp talks up ´South Coast Mariners´ role|
|Real Madrid can cope without Benzema - Navas|
|Ronaldo returns for Madrid, but Benzema will miss Bernabeu clash|
|Ranieri wants happy players for title defence|
|Kosovo win vote to become UEFA member nation|
|Drinkwater: Leicester title is mad, bonkers|
|Morgan predicts tear-stained Premier League trophy|
|Transfer market travails and the empire striking back: What next for Leicester City?|
|Toure trains ahead of Real Madrid clash|
|Guardiola´s rotation policy a potential own goal - Magath|
|Ballack backs Atletico to prove too strong for Bayern|
|Messi agreed with Olympics snub - Martino|
|Benzema misses Real Madrid open training|
|Ranieri: We want to improve|
|Ronaldo: Like it or not, I´ll go down in history|
|Strootman delighted with return to Roma starting XI|
|Laporte dismisses Manchester City rumours|
|Ranieri has silenced critics, says Kisnorbo|
|Van Gaal: I am one of the best managers in the world|
|Santa Cruz: Guardiola will bring better football to City|
|Guardiola always a bit anxious - Kahn|
|Kisnorbo: No one will forget Leicester´s fairytale run to Premier League glory|
|Rodgers backs Klopp´s handling of Sturridge|
|Wright: No one would have touched Kante and Co.|
|Smalling: Captaining United an honour|
|No surprises in Mexico´s 40-man Copa squad|
|Juanfran: We are a team of details|
|Stepanenko: My friendship with Yarmolenko is over|
|Leicester fan Martinez: I am glad it did not happen in Germany|
|Schwarzer has shown age is just a number - Kisnorbo|
|Mangala: City want to make history in Champions League|
|Lineker struggling to believe Leicester success|
|Carrick: Top four not gone yet|
|De Gea named United´s player of the year|
|Dundee 2 Dundee United 1: Visitors relegated|
|King delighted to crown Leicester rise with title|
|Ranieri: I knew I would win a title eventually!|
|Soccer world reacts to Leicester´s remarkable Premier League title|
|Serie A Review: Strootman starts as Roma fight back again|
|Leicester success a ´good omen´ for Selby|
|Kane: Chelsea celebrated like they won title|
|Thumping Man City, edging Tottenham and five matches that won Leicester the Premier League|
|Vardy marvels at Leicester´s finest hour|
|Ranieri called me to say thanks, reveals Hiddink|
|Leicester did the impossible - Morgan|
|Terry: Leicester title triumph gives hope to smaller sides|
|Pochettino proud as Spurs fall short|
|Savage: Leicester title a key moment in Premier League history|