Manchester City's fingertip hold on their Premier League title was further loosened when a 2-0 loss at Everton followed by runaway leaders Manchester United's 1-0 win over Reading left them praying for a football miracle.
Substitute Nikica Jelavic sealed victory deep in stoppage time after being set up by a rampaging Marouane Fellaini.
United needed no second invitation to open a 15-point lead in the title race although only Wayne Rooney's deflected early shot separated them and second-bottom Reading at Old Trafford.
Alex Ferguson's side never required top gear as they rolled on towards a 20th English title with their 24th victory in 29 league games this season, although the Scot refused to accept that the race was won.
"We have got Sunderland away in our next game, which is always a tough place to go, and then we face Manchester City at home," he told ESPN.
"You don't get points and medals for being complacent," added Ferguson whose side have 74 points ahead of City on 59.
Everton briefly rose above Arsenal into fifth spot with 48 points in the battle for a top-four position but the Gunners responded with a 2-0 victory at Swansea City.
That took Arsene Wenger's side to 50 points within two of fourth-placed Chelsea, who host West Ham United on Sunday, and four behind local rivals Tottenham Hotspur, who are third ahead of their home game with Fulham also on Sunday.
Boosted by a surprise, if ultimately fruitless, Champions League win in their last 16, second leg tie at Bayern Munich on Wednesday, Arsenal struck late through Nacho Monreal and Gervinho.
"It was a difficult game away to Bayern in midweek. The spirit we showed today was fantastic. We're up for the battle," Wenger told Sky Sports.
Liverpool lost 3-1 at Southampton to virtually extinguish their top-four hopes and hand Saints a major boost in their bid to steer clear of trouble at the bottom of the table.
In a thrilling relegation scrap, Aston Villa clawed their way to a vital 3-2 victory over bottom club Queens Park Rangers.
Christian Benteke scored the winner after 81 minutes to leave QPR seven points adrift of the safety zone.
QPR, seeking a third consecutive league win, led 1-0 thaansk to Jermaine Jenas and then equalised through Andros Townsend having gone 2-1 behind before Benteke grabbed his 13th league goal of the season.
Everton, one week after being booed and heckled by their fans in an embarrassing 3-0 FA Cup sixth round defeat at home to struggling Wigan Athletic, produced a gutsy performance to remain in contention for a top-four finish.
"Last week was disappointing but we showed when we are at the races we are a match for any team," said Osman, who is in England's squad for this month's World Cup qualifiers against San Marino and Montenegro.
His strike was a special one, the midfielder having received the ball from Seamus Coleman 25 metres out before lashing a shot past helpless England keeper Joe Hart.
City missed the drive of the absent Yaya Toure in midfield as Everton dominated, although they showed more desire after the break and were pressing hard for an equaliser when Pienaar raked his studs down the shin of Javi Garcia.
The inevitable red card merely galvanised Everton, with second-choice keeper Jan Mucha exemplifying their commitment with a double save from Carlos Tevez and James Milner.
City were denied a blatant late penalty when Tevez's shot was blocked by the arm of Fellaini, with the referee ruling it had been outside the box and awarding only a free kick.
Jelavic's effort rounded off a dark day for the champions whose manager Roberto Mancini declined to give his post-match television interview, instead sending out assistant David Platt.
"He's angry and he's taking stock," Platt said. "He wants to calm down rather than say anything that will get him in trouble.
"We got outworked by Everton but there is no doubt in my mind about the handball. It was three yards inside the area and though perhaps the performance didn't deserve it, we could have got a bit more out of it if that decision had gone for us."
United were uninspired against struggling Reading, who sacked manager Brian McDermott this week and put academy manager Eamonn Dolan in caretaker charge.
It needed some dazzling play from Rio Ferdinand, recalled by England this week after a long absence from international duty, to help break the deadlock, the veteran defender's elegant run setting up Rooney to score via a deflection in the 21st minute.
Southampton beat Liverpool thanks to goals from Morgan Schneiderlin, Rickie Lambert and Jay Rodriguez with Philippe Coutinho pulling one back for the seventh-placed visitors.
In the day's other match, Stoke City and West Bromwich Albion played out a tepid 0-0 draw.
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