The Gunners are looking to finish in the Premier League’s top four this season for the first time since 2015-16 after the north London regressed under Arsene Wenger.
Emery’s men have made significant progress in the Premier League despite losing to Manchester City and Chelsea FC in their opening two fixtures.
Arsenal won their next seven Premier League games to hoist themselves up the top flight table to make a push towards the Champions League spots.
The Gunners dropped points in a 2-2 draw with Crystal Palace at Selhurst Park last month before Arsenal battled from 1-0 down to rescue a 1-1 draw with Liverpool FC.
Alexandre Lacazette’s equaliser cancelled out James Milner’s opening goal to secure a point and prove that Emery’s side are developing a backbone under the Spanish head coach.
Arsenal will take on Wolverhampton Wanderers in their next Premier League fixture on Sunday, looking to extend their unbeaten run to nine games.
Former Gunners striker Hartson believes will struggle to ease past Chelsea FC, Manchester United and Tottenham Hotspur in the top-four race to secure a spot in the Champions League next term.
“It’s very similar to last season where they had a brilliant Europa League campaign,” Hartson told StarSport.
“I did a lot of co-commentary for Arsenal’s group games last season and I thought they found it relatively easy, although no game’s easy but they won pretty well.
“And I think they’ve had a pretty good start under Emery, and I think a lot of people, including myself, ruled them out of even a top four place.
“The Europa League is obviously very important for Arsenal, because if they win it of course they get that Champions League spot.
“And with the Premier League being so competitive, if Arsenal are going to finish in the top four, that means they’re going to have to finish above United, who I believe will still come strong, and finish above a Tottenham or a Chelsea and we see how strong and well they’re going.
“It looks like Man City and Liverpool are almost gimmes for the top four, so it looks like it’s just a case of which of them two will go all the way and win the title, I believe.
“So if Arsenal are not going to win the Europa League, it might be another season without the Champions League, and a club the size of Arsenal really needs to be in the Champions League.
“This will be three years out of the Champions League if they don’t win the Europa League or finish in the top four.
“And a club the size of Arsenal with the investment they need to make – they keep buying big players and pay the big wages – it’s another season where they’ll maybe have to look at cutting the purse strings because they wouldn’t have that Champions League money.
“Now every club works within them restraints.”
Arsenal signed Juventus defender Stephan Lichtsteiner, Bayer Leverkusen goalkeeper Bernd Leno, Sampdoria midfielder Lucas Torreira, Borussia Dortmund defender Sokratis Papastathopoulos and Lorient teenager Matteo Guendouzi in the summer transfer window.
The Gunners haven’t won the Premier League title since 2003-04 when Wenger’s side finished the season unbeaten thanks to the excellent performances of club legends such as Thierry Henry, Patrick Vieira and Robert Pires.
Emery will be hoping that some leaders emerge in the current Arsenal squad to emulate the likes of Henry and Vieira, with Torreira’s tenacious performances in the middle of the park suggesting he could become a leader on the pitch
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