The Gunners lead were 1-0 up until the 83rd minute but a howler from Bernd Leno allowed Jorginho to tap in from close range before Tammy Abraham sealed victory for the hosts at Stamford Bridge.
On the whole it was an encouraging performance for Arteta and Shearer thought there were ‘so many signs of encouragement’ before problems of the past came back to ‘haunt’ them.
And he thinks Arteta will need to invest in defensive reinforcements if they’re to match his ambitions.
He wrote in The Sun: ‘For the first 80 minutes at the Emirates there were so many signs of encouragement for Arsenal but, in the end, the same old problems that have plagued them for years came back to haunt them.
‘The whole team appeared organised for large parts and it looked as though they had a different attitude.
‘They put in a huge amount of effort, which they have regularly lacked in the past.
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‘Then, with just seven minutes to go, the old Arsenal came back to bite and they self-destructed.
‘Firstly, you can’t legislate for individual errors with Bernd Leno, who has rarely been the culprit, gifting Chelsea an equaliser.
Then, instead of settling for 1-1 which would have been a good result, they went charging up the pitch at the end and left themselves wide open at the back.
‘One thing Arteta will now definitely know is that he desperately needs to bring new defenders in if they are to kick on.’