The Gunners are flying under Unai Emery this season, with Arsenal currently on a 15-game unbeaten run. However, Arsenal still trail champions Manchester City by six points.
City, Liverpool and Chelsea all remain unbeaten this season as the Premier League title race heats up.
Pep Guardiola and Jurgen Klopp have splashed the cash in recent seasons, with both City and Liverpool smashing their transfer records this year.
City brought in Riyad Mahrez from Leicester for £60m in the summer, while Liverpool spent £75 on Virgil van Dijk in the January transfer window.
The Reds’ continued to spend in the summer, with Liverpool landing Alisson in a world-record goalkeeper deal worth £66.8m, while also splashing £52m on Naby Keita.
Arsenal also broke their transfer record this year with the £55m purchase of Pierre-Emerick Aubameyang, who has impressed in north London. However, the Gunners are far behind City, Liverpool and Manchester United when it comes to spending big in transfer windows.
And BT Sport analyst Hartson reckons Emery must go in for the best players in the world, a player of Real Madrid star Bale’s stature, if Arsenal are to win their first Premier League title since 2004.
When asked how far away Arsenal are for challenging for the title, Hartson exclusively told Express Sport: “Right now Man City and Liverpool are a fair way away from the rest.
“The football they play and the players that they have. Most teams are playing for third. Chelsea, Tottenham, United.
“They won’t admit it but deep down they’re wishing they had a [Sergio] Aguero or a [Kevin] De Bruyne.
“How far are Arsenal away? I think they’re a few years behind in terms of challenging for the title. Top four would be a great success because they’ve missed out the last two seasons. They don’t want to make it three. They’ll do their upmost to get in there.
“Without going to far ahead, if they get into the top four, they will have to finish above two great teams.
“In terms of the title, there’s going to have to be some money spent, they must back Emery in the transfer market. You know Man City are going to go in for the best players on the planet. Arsenal don’t do that.
“Liverpool do now, they just spent £60m on a goalkeeper, £75 on Van Dijk, £50m on Keita – and they’ve got three strikers that are incredible. Right through their spine, they are superb.
“No disrespect to Arsenal, if say for arguments sake, a Gareth Bale becomes available [they won’t go in]. I know he’s ex-Spurs and it may not happen.
“But if a top player like that became available and he’s £95m with £40m wages over the next four years, will they go in for him? They might not.
“But someone like City would and they have. It’s going to take investment, time with Emery and backing from the football club for Arsenal to come close to challenging again.”
Bale is now Real’s main man at the Bernabeu following Cristiano Ronaldo’s departure to Juventus in the summer.
However, the Wales international isn’t a fan favourite at Real, with supporters often booing the 29-year-old if he fails to perform.
Bale, who has been heavily linked with a move back to the Premier League in recent years, has netted five goals in all competitions for Real this season.
Arsenal are back in action on Sunday afternoon, with the Gunners hosting Wolves in the Premier League.
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