Liverpool were the big losers after the big four teams all played each other on Sunday.
But it's too early to write off their title hopes yet.
In fact, they probably came away from Stamford Bridge wondering how they did not win the game, never mind lose it.
They created five great opportunities and should have had a penalty.
But, as we always say, the sign of a great team is one that wins when they're not playing particularly well.
They've got a huge week coming up, with Newcastle and Tottenham both coming to Anfield and six points is a priority.
Chelsea, this season, have not been anywhere near the dizzy heights they reached last season, when they controlled games.
This season, they've not had total control in any match and could have been beaten on Sunday. But they've ground a result out once again.
And it wasn't all luck. Didier Drogba's performance on Sunday was as good as any I've seen him produce.
Not only did he score a wonder goal, but his touch and technique were both spot on.
When he's on form like that, he gives Chelsea an extra dimension with his height and strength.
In contrast, Andriy Shevchenko looks - so far at least - a shadow of the player we expected him to be.
I thought it was a better game up at Old Trafford between Manchester United and Arsenal.
For the first time this season, Arsenal were really allowed to play.
United were at home, with four wins under their belt already, with more than 70,000 backing them. The crowd wants entertainment and it wants attacking football.
<TABLE cellSpacing=0 cellPadding=0 width=208 align=right border=0><TBODY><TR><TD width=5></TD><TD class=sibStdQuote><DIV><DIV class=mva><DIV id=q1></DIV>Portsmouth are still on top, of course. They're not going to stay there, but they have half a chance of finishing in the top half <DIV id=q2></DIV><BR clear=all></DIV></DIV></TD></TR></TBODY></TABLE>United tried to supply that, but that allowed Arsenal to play.
And the Gunners showed they're still the best team for movement. They play quick one and two-touch football.
It made the game more open than in Arsenal's three previous league matches.
Most teams will be defensive against Arsenal.
The most effective way to play against Arsene Wenger's side is the way Aston Villa played, the way Middlesbrough played and the way Manchester City played - all with some success.
Against the big teams away Arsenal will have a better chance of playing their natural game.
If they go to Stamford Bridge and Anfield, those teams are committed to coming out and playing.
It was a great performance by Arsenal and a massive victory for them, because if they'd been beaten they were struggling as far as the league was concerned.
I don't think Sir Alex Ferguson will be all that worried, mind you.
United had chances and good possession as well. On the day, Arsenal were probably the better team.
But when it was 0-0, it could have gone either way.
If we learnt anything about the two big games yesterday, it was that there really is not much between the four sides.
But Chelsea's ability to grind out results might be the difference between winning and losing the title.
Portsmouth are still on top, of course. But they're not going to stay there.
But if you go back to the dark days of last season when they seemed dead certs for relegation, who would have thought that they would be sitting top of the table after five matches with 13 points and no goals against?
Who would have bet that they would even finish in the top half of the table this season? But with the solid foundation, they've got half a chance of doing that.
It's fantastic for the players, fantastic for Harry Redknapp but, more importantly, for the supporters.
But it's too early to write off their title hopes yet.
In fact, they probably came away from Stamford Bridge wondering how they did not win the game, never mind lose it.
They created five great opportunities and should have had a penalty.
But, as we always say, the sign of a great team is one that wins when they're not playing particularly well.
They've got a huge week coming up, with Newcastle and Tottenham both coming to Anfield and six points is a priority.
Chelsea, this season, have not been anywhere near the dizzy heights they reached last season, when they controlled games.
This season, they've not had total control in any match and could have been beaten on Sunday. But they've ground a result out once again.
And it wasn't all luck. Didier Drogba's performance on Sunday was as good as any I've seen him produce.
Not only did he score a wonder goal, but his touch and technique were both spot on.
When he's on form like that, he gives Chelsea an extra dimension with his height and strength.
In contrast, Andriy Shevchenko looks - so far at least - a shadow of the player we expected him to be.
I thought it was a better game up at Old Trafford between Manchester United and Arsenal.
For the first time this season, Arsenal were really allowed to play.
United were at home, with four wins under their belt already, with more than 70,000 backing them. The crowd wants entertainment and it wants attacking football.
<TABLE cellSpacing=0 cellPadding=0 width=208 align=right border=0><TBODY><TR><TD width=5></TD><TD class=sibStdQuote><DIV><DIV class=mva><DIV id=q1></DIV>Portsmouth are still on top, of course. They're not going to stay there, but they have half a chance of finishing in the top half <DIV id=q2></DIV><BR clear=all></DIV></DIV></TD></TR></TBODY></TABLE>United tried to supply that, but that allowed Arsenal to play.
And the Gunners showed they're still the best team for movement. They play quick one and two-touch football.
It made the game more open than in Arsenal's three previous league matches.
Most teams will be defensive against Arsenal.
The most effective way to play against Arsene Wenger's side is the way Aston Villa played, the way Middlesbrough played and the way Manchester City played - all with some success.
Against the big teams away Arsenal will have a better chance of playing their natural game.
If they go to Stamford Bridge and Anfield, those teams are committed to coming out and playing.
It was a great performance by Arsenal and a massive victory for them, because if they'd been beaten they were struggling as far as the league was concerned.
I don't think Sir Alex Ferguson will be all that worried, mind you.
United had chances and good possession as well. On the day, Arsenal were probably the better team.
But when it was 0-0, it could have gone either way.
If we learnt anything about the two big games yesterday, it was that there really is not much between the four sides.
But Chelsea's ability to grind out results might be the difference between winning and losing the title.
Portsmouth are still on top, of course. But they're not going to stay there.
But if you go back to the dark days of last season when they seemed dead certs for relegation, who would have thought that they would be sitting top of the table after five matches with 13 points and no goals against?
Who would have bet that they would even finish in the top half of the table this season? But with the solid foundation, they've got half a chance of doing that.
It's fantastic for the players, fantastic for Harry Redknapp but, more importantly, for the supporters.