Robbie Keane's arrival last summer was supposed to be the missing piece in Liverpool's title picture but the great irony of their season may now be that his departure could inadvertently win them the Premier League.

Keane remains a top-class forward but it can be no coincidence that since his departure, the Reds have found their best form - with Steven Gerrard and Fernando Torres fit and at the fulcrum of the revival.

Liverpool clearly suffered from the absence of their best two players but no matter what Keane's contribution was in any match following his £20.3million move from Tottenham, he was always the talking point.

Rafa Benitez had to field endless questions about the Irishman and it was draining for the manager and player, who both deserved better.

Keane, who has since gone back to Tottenham where he is proving his quality, was bought to play off Torres, but Gerrard was consequently pushed back into midfield which only stunted the effectiveness of their captain and contributed to a lack of fluidity.

But Benitez's best team is now obvious. Rafa's 4-2-3-1, with Gerrard pushed further forward behind Torres, is now a devastating system that maximises everything from the players he has at his disposal - as was demonstrated by the England player's superb hat-trick yesterday against Aston Villa.

The 'Keane' question no longer exists and everyone seemingly knows their place within the squad.

That clarity of thinking is at odds with Sir Alex Ferguson's United at present and I believe Liverpool will maintain this push and pip the champions because they are now playing with the belief that the Premier League title is in sight.

Maybe the international break is just what United need - a week's training together didn't work following their thrashing by Liverpool at Old Trafford last week and it might be good to get away.

The training ground is a great environment to be in when you are winning and you see the best of everybody on a daily basis. But every player has their individual problems and when results start to go against you, they all become bigger and can fester.

Maybe that has happened at Old Trafford. And for the first time in a number of years, it is difficult to for Ferguson to pick his first choice line-up.

While that can of course be a good thing, when the big matches come around it is impossible to keep everyone happy and maintain consistency with harmony.

Whereas Benitez will hope his players avoid injury, Ferguson must now prove he can juggle one of the biggest squads he has ever had.

This is the same problem that Guus Hiddink now faces at Chelsea.

Michael Ballack has been deployed in a deep-lying midfield role - where John Obi Mikel usually plays - in recent matches and it was arguably their undoing in the defeat at Tottenham on Saturday.

I would like to see Michael Essien in a deeper position. He can spring from his own half when the situation requires and would provide a better defensive shield than Ballack.

Saturday was obviously a missed opportunity for them and the title may just be beyond them now. Conversely, I was pleased to see two of the stars of the Spurs side that won at White Hart Lane earn international recognition when Ledley King and Aaron Lennon were called up by England last night.

Fabio Capello probably wants to find out a little about what going on medically with King, as he only hears about his chronic knee problem from Spurs.

There is no doubt he is England class but in a major tournament you play every three days and his fitness problems raise a huge question mark over his inclusion at the 2010 World Cup.

I am told he rarely trains and his focus is obviously on extending his playing career. That may be more important to him than representing his country.

Across North London at Arsenal, Arsene Wenger has set his sights on third place after overhauling Martin O'Neill's Aston Villa. The Gunners are the only unbeaten Premier League side in 2009 and are on their longest League run without defeat since the famous 'Invincibles' season of 2003/04.

Villa look to be running out of steam and have never won League game in the month of March since O'Neill took over in 2006.

Arsenal, though, are developing all the time and have a host of youngsters earning the right to play in the team.

Abou Diaby has impressed me the most in recent matches - he is like Patrick Vieira but with pace.

Cesc Fabregas may take a little time to settle back in after four months out with injury but his return is a massive boost and alongside Diaby, they will give Arsenal a steel and guile in midfield next season, even though they have left it too late to catch the top two.