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'
|Australia 2 South Korea 1 (aet): Troisi seals Socceroos´ maiden Asian Cup title|
|Ibrahimovic questions PSG fans|
|Azpilicueta anticipating ´weird´ Lampard return|
|Sinclair: Milner praise for Villa made my decision easy|
|Van Gaal fumes at questions on Herrera´s future|
|Cork excited about new challenge|
|Arsenal still gunning for glory - Gibbs|
|Quinteros named Ecuador coach|
|Sturridge eager to prove fitness|
|Blanc: ´We were expecting better´|
|Hecking proud of Wolfsburg|
|Boateng urges Bayern to learn from Wolfsburg thrashing|
|Sporting Braga 1 Moreirense 0: Santos the hero for hosts|
|Cordoba complete triple swoop, Levante bring in two|
|Partick Thistle 0 St Mirren 1: Debutant Dayton the hero|
|Rayo Vallecano 1 Deportivo La Coruna 2: Borges debut double downs hosts|
|Bournemouth 2 Watford 0: Championship leaders stroll to success|
|Dordrecht 0 Heerenveen 0: Visitors´ woes compounded by Sinkgraven sale|
|Paris Saint-Germain 1 Rennes 0: Lavezzi goal enough for champions|
|Palace confirm Souare capture|
|Barcelona v Villarreal: Xavi looking to put high-flyers in their place|
|Simeone denies gesture towards referee|
|Wolfsburg 4 Bayern Munich 1: Dost and De Bruyne at the double as hosts honour Malanda|
|Ben Arfa ineligible to play for Nice|
|Ginola calls time on FIFA presidency bid|
|Cork seals Swansea switch|
|Arsenal v Aston Villa: Wenger lauds team spirit|
|Strootman out for longer than expected|
|Southampton v Swansea City: Monk eager for return to form|
|Injury blow for Southampton striker Long|
|Montella confirms Cuadrado will join Chelsea|
|Bordeaux bring in Chantome from PSG|
|Huth suspended for two matches over tweets|
|Udinese v Juventus: Pirlo not taking Serie A lead for granted|
|Carlisle to return home|
|Prince Ali outlines campaign after submitting FIFA president bid|
|Costa must improve behaviour - Pellegrini|
|Olic seals Hamburg return|
|FIFPro planning legal action to protect unpaid players|
|Burnley rule out Liverpool move for Ings|
|Pochettino fumes at Tottenham schedule|
|Cork set for Swansea switch|
|Hull left in the cold by local gas board|
|Ancelotti: No repeat of Ronaldo indiscretion|
|Murray signs Palace extension|
|Garcia: Roma will sign a replacement for Destro|
|Sassuolo v Inter: Ranocchia hopes turning point has come|
|Congo v Democratic Republic of Congo: Neighbours clash in AFCON quarter-final|
|Fletcher in West Ham talks|
|Tunisia v Equatorial Guinea: Favourites wary of hosts|
|Carrick to miss four weeks|
|Figo submits bid for FIFA presidency|
|Costa hit with three-match ban|
|Villa confirm Sinclair loan|
|Hull agree fee for N´Doye|
|Milan clubs should merge, says agent Raiola|
|Redknapp brands Fer speculation ´absolute rubbish´|
|Destro completes Milan move|
|Iraq 2 UAE 3: Khalil´s brace sees off Iraqis|
|Ward-Prowse signs Southampton deal|
|Mandanda: Marseille will turn it around|
|Fuchs backs Schalke goalkeeper Giefer to shine|
|Wenger unlikely to risk Sanchez, could start Gabriel|
|Newcastle would need ´ridiculous´ bid to sell Sissoko|
|Kramer sure of sustained Champions League challenge|
|Sturridge would have steered Liverpool to Wembley - Rodgers|
|South Korea claim underdog status|
|We can handle the pressure, says Postecoglou|
|Cheyrou joins Toronto|
|AFC boss rejects Australia expulsion claims|
|Australia v South Korea: Socceroos eyeing maiden Asian Cup|
|Wolfsburg plan Malanda tribute|
|Blanc: Ibrahimovic, Cavani need to improve partnership|
|NBA´s Kings invest in Sacramento Republic|
|Djukic slams Ronaldo as ´ugly and conceited´|
|Marcelino hails Villarreal´s historic achievement|
|Destro: I want to show Milan are great|
|Copa del Rey Review: Aduriz breaks drought to send Bilbao through|
|Blaszczykowski to miss Leverkusen clash|
|Villarreal swoop for Bailly|
|CAF to consider alternatives to drawing lots|
|Ginola ´not giving up´ on FIFA presidency bid|
|Eto´o backs Sampdoria´s European dream|
|Chelsea v Manchester City: Costa out and Fabregas doubtful for title showdown|
|Sunderland v Burnley: Poyet calls for change in mentality|
|Serie A Preview: Crisis clubs meet as Parma head to Milan|
|West Brom v Tottenham: Pulis excited by McManaman arrival|
|Ginola campaign cancels crowdfunding page|
|Stoke City v QPR: Hughes hopeful of Diouf boost|
|Manchester United v Leicester City: Pearson has no time for fond memories|
|Thai consortium completes Wednesday purchase|
|Wigan exodus continues as Ramos joins Levante|
|Crystal Palace v Everton: Martinez hoping to reap Qatar training rewards|
|Liverpool v West Ham: Allardyce backs Carroll to shine on Anfield return|
|Strootman injury ´nothing serious´|
|Pearson backs Kramaric to adapt quickly|
|Hull City v Newcastle United: Carver calls for repeat KC Stadium rout|
|Rodgers not expecting immediate Sturridge impact|
|Palace land free agent Ameobi|
|Guinea progress past Mali in drawing of lots|
|Strootman requires surgery|
|Mathieu reveals details of Luis Enrique-Messi bust-up|
|New Inter signing Brozovic wants to be the next Frank Lampard|
|Bayer Leverkusen v Borussia Dortmund: Visitors aim for fresh start|
|Eibar v Atletico Madrid: Capa up for a fight|
|Whelan and Crouch sign new Stoke deals|
|Mutch joins Palace from QPR|
|Eriksen delighted by League Cup double|
|Real Madrid v Real Sociedad: Moyes´ men out for rare Real double|
|Nolan impressed by Carroll attitude|
|Wenger: Gabriel will adapt to English football|
|Destro says yes to Milan move|
|Allardyce not expecting Sakho ban|
|Ribery sidelined for three Bayern Munich matches|
|Cahill refuses to rule out retirement after Asian Cup final|
|Pogba to leave Juve by end of next season - Agent|
|Martinez not planning Eto´o replacement|
|Blatter formally submits bid to remain FIFA president|
|Puncheon predicts ´great times´ for Palace|
|Donadoni has no plans to leave Parma and criticises Cassano|
|Mangala: My first season at City could have been better|
|UAE v Iraq: Rare podium finish on offer|
|Ryan spurred on by Australia´s 2011 heartbreak|
|Montella will not sell Cuadrado cheap|
|Mali, Guinea furious with tie-breaking procedure|
|Luis Enrique defends Neymar´s behaviour|
|Gabi: Referee lacked personality|
|Chile 3 USA 2: Gonzalez´s brace extends Americans´ pain|
|Franjic cleared of serious injury|
|Our progression was deserved - Pochettino|