Substitue Vladimir Smicer volleyed a superb injury-time winner as Liverpool beat Chelsea 1-0 to go top of the Premiership yesterday.
Smicer, who came on after Liverpool lost England midfielder Steven Gerrard to a recurrence of a groin injury - he misses Wednesday's international against Italy - smashed in a cross from Emile Heskey as the hosts secured a barely-deserved victory.
The win put Liverpool top of the table with 65 points, one ahead of champions Manchester United, who lost 1-0 to Middlesbrough on Saturday. Arsenal, third on 63 points, seem best-placed, as they have two games in hand on both their title rivals.
Seldom can a championship have swung so significantly towards one of the contenders at this stage without their having to make an active contribution, Arsenal having been involved in beating Newcastle 3-0 to reach the FA Cup semi-finals on Saturday.
Arsenal should be able to begin stealing a march on their rivals when Manchester United and Liverpool are involved in the Champions League quarter-finals.
Their visit to Old Trafford was to have been taken a fortnight on Saturday, but Arsenal will be involved in the FA Cup semi-finals that weekend.
The game with United, which might now have to be put back until after the FA Cup final, could turn out to be a postscript to the championship rather than a decider.
Alex Ferguson said on Saturday that the destiny of the title is now in the Londoners' hands, but Liverpool's assistant manager, Phil Thompson, was in no mood for concessions yesterday, saying: "It's nice at this stage of the season to be top. There's still a little bit to do, but we played a very difficult team today and it can give us heart for the remaining games of the season.
"We want to win both the Champions League and the Premiership, and the belief is there that we can do it.
"Once again the players are showing what they did last year. Game after game they have got the concentration and the focus to go for it.
"It's not new to us because we showed it last year when there was that third place to fight for. We handled it brilliantly then and we can do it again."
Midfielder Danny Murphy - recalled to the England squad in place of Gerrard - was also in bullish mood, saying: "Hopefully this will make a massive difference. If Arsenal win all their games no one can do anything about it, but they've still got to go to Old Trafford and United have to go to Leeds next week, so points could still be dropped. With United losing, it was important that we capitalised on it."
United defender Gary Neville has said that if his side fails to win the title, it will be because of their poor home form.
Prior to this season United had lost just three league games at Old Trafford between March 1998 and May 2001.
Now they have lost five in the last five months. The last time they lost so many times at home was when they finished a lowly 13th in the 1989-90 season.
Neville said: "To be honest losing those three games at home to West Ham, to Bolton and now to Middlesbrough makes it very difficult for us."
"It's not just the actual defeats, it's the teams that we've been beaten by at home and you don't expect us to be beaten in that way.
"There's nine points gone and if they were on our total we would have the championship won already.
"But for some reason we have not been able to win those three games. I think people would have been thinking that these were home bankers."
In yesterday's other game, Tottenham Hotspur beat Fulham 2-0 at Craven Cottage, with goals from England striker Teddy Sheringham and Uruguayan Gus Poyet inflicting the home side's sixth consecutive league defeat.
Fulham are not yet safe from relegation, and manager Jean Tigana said: "We now need to win at home and take some points away. I think we need six or seven morepoints - then it will be possible to stay at the top level."
