The north London side were understood to have the first option to re-sign Fabregas after it became clear he was to leave Barcelona in the summer of 2014.
However, Wenger opted not to bring the former Arsenal captain back to Emirates Stadium, before the playmaker eventually ended up signing for Arsenal’s London rivals Chelsea.
And Hartson feels that the Frenchman opted not to bring Fabregas back to the club because he felt that his arrival would have prevented his current players from developing.
Speaking to the Daily Star, Hartson said: “Wenger will never want to buy players too similar to what he’s already got. He won’t go out and spend all that money just to get someone who is already as good as what we’ve got.
“I think that’s the reason why Wenger didn’t try to bring Fabregas back a couple of years ago before he went to Chelsea. We had players like [Aaron] Ramsey, [Francis] Coquelin, etc and Wenger was thinking ‘I want to bring these young players through’.
“He would have thought maybe Fabregas will stunt these guy’s developments and affect their chances for first team football.”
Fabregas spent eight seasons at Arsenal before returning to Barcelona.
Arsenal ended up in second place in the Premier League table last season after they pipped local rivals Tottenham Hotspur on the final day of the campaign.
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