Claudio Ranieri is surprised Arsenal failed to win the title during his 11-year spell away from the Barclays Premier League.
When Ranieri left English football in 2004, the Gunners had just gone through the entire league season unbeaten.
Ranieri's Chelsea team finished runners-up that year, 11 points behind their London rivals, and reached the semi-finals of the Champions League for the first time in the club's history, but it was not enough for the Italian to keep his job and he was replaced by Jose Mourinho.
In the intervening time, while Ranieri has undertaken club jobs in Spain, Italy and France and been in charge of the Greece national team, the closest Arsenal have come to being champions again was when they were second behind Chelsea in Mourinho's maiden campaign.
However, ahead of Leicester's home game against Arsene Wenger's team on Saturday, Ranieri believes Arsenal are ready to mount a serious title challenge once again.
"When I was at Chelsea, they were 'the Invincibles' said Ranieri.
"That was an unbelievable achievement, so it is surprising they have not won the league since.
"I don't know why Arsenal have had to wait so long, because Arsene Wenger is a good manager and he brings in good players. But maybe it is not so easy to replace players such as Thierry Henry, Dennis Bergkamp, Fredrik Ljungberg and all the defenders.
"But now, again, Arsenal is a very good team (who) we respect a lot. (They are) smart, fast, technical - everything. They are fantastic, good quality. (They) move the ball very well, very quickly.
"They are ready to fight again for the title and it will be a very good match."
It might be said Arsenal are preparing to face Leicester's 'Invincibles', with Ranieri's team holding the Premier League's only remaining unbeaten record following Manchester City's home defeat to West Ham last weekend.
The 63-year-old chuckled at the suggestion before acknowledging his own poor record against Wenger's Gunners.
He said: "I have not such a good record against Arsenal. It is bad. If I remember well I didn't win for 17 matches, or 16 matches." It is actually one win in 14 meetings.
He added: " In my time at Chelsea I only managed to beat them once, but I won the last one in the quarter-final of the Champions League.
"It is a bad record but every match was very good, they won or drew, but the matches were very open."
Ranieri will make several changes to his starting line up for the visit of Arsenal after swapping 10 players against West Ham in the Capital One Cup in midweek.
T he likes of Kasper Schmeichel, Ritchie De Laet, Wes Morgan, Danny Drinkwater, Ngolo Kante, Riyad Mahrez and Jamie Vardy are all expected to return to the team but on-loan winger Nathan Dyer (knee) remains out injured.