Former Arsenal striker John Hartson believes that Alexandre Lacazette must score 25 goals this season - or else.

Lacazette is currently the main striker at the club, with fellow attacker Pierre-Emerick Aubameyang often playing wide to accommodate him.

And Hartson knows that if Lacazette does not score a lot of goals, his place in the team will be under threat.

BT Sport analyst Hartson exclusively told Starsport: "If he can get 25 goals this season, he's done his job.

"You look at Arsenal's strikers in the past - I never achieved anything at Arsenal, I achieved at Celtic, I achieved a lot at West Ham - but what I'd say is you've got to keep banging them in.

"He's got to keep putting something in Emery's head every week, make him think 'I can't leave Lacazette out, I cannot leave his movement out, I cannot leave his goalscoring abilities out, he's too important for me to leave out of the team'.

"He came for £55m, a big price tag on his head. I felt Arsenal should have gone and got him a few years prior to when we did, it's just a case of not putting the money up early on, which was a criticism you could say about several players.

"But I think since he's arrived, 17 [goals] last season, but this season he's been on fire. He's a goalscorer, he can score all types of goals, he's got great movement, and I'm glad he's doing well.

"But 25 goals, I think if you ask him himself, that is a great return. The Wrightys used to do it, the Henrys used to do it, Van Persies used to do it - so if he's going to be put down as an Arsenal great and get Arsenal into places where they can eventually win trophies, I think 25 [will do that]."