Arsenal fans were hoping this was going to be their season after pushing Manchester City close in each of the past two campaigns.
And with City faltering – on the back of four consecutive defeats in all competitions – this might have been their ideal chance.
But Liverpool are performing better than anyone could have imagined under new boss Arne Slot, with 28 points out of a possible 33.
And the Gunners trail the leaders by nine points at the end of a weekend for the first time since the final day of 2021-22, when they finished 24 points behind Manchester City.
They looked dejected as the final whistle went at Stamford Bridge.
Walcott said: “The difference with Arsenal at this moment in time is that they are lacking in goals, while they are not conceding many – but at this point of the season it’s important to factor in who they have played.
“I would say that, so far, they have played tougher teams – they have played six of last season’s top 10, and five of those games have been away from home.
“Plus, most of the time they have been without their main player, Martin Odegaard, and they are still where they are.”
Captain Odegaard made his first Premier League appearance since August against Chelsea and set up Gabriel Martinelli’s opening goal.
Walcott added: “People tend to forget all of that when they look into how Arsenal are not playing at the same level they were at last year, but for me it is one of the reasons not to write them off in the title race.”
Gunners legend Paul Merson, speaking on Sky Sports, said: “He [Arteta] has got to make sure it gets down to six points rather than go to 12.
“I think they’ll do well to catch Liverpool now. It might stay at nine until the end of December. If it goes to 12 then it’s finished.”
Can Arsenal do it? Well, history is not on their side.
Excluding teams with games in hand, nobody has ever won the Premier League title after being nine (or more) points off top with 11 games gone.
Manchester City managed it in 2013-14 but leaders Arsenal had played 12 games by that stage.
Speaking about his title rivals, Arteta said his team need to “win, win, win, win and win, because these guys don’t stop winning”.
If they were to win every remaining game this season they would end on 100 points, with Liverpool’s current form putting them on course for 97 points.