The Gunners beat Bournemouth 2-0 on Sunday afternoon.
The Gunners were one of the favourites for the title this season, with an impressive end to last season and the addition of Petr Cech making many choose them among the runners for the title.
Recent weeks have seen them struggle though, as they went three games without a goal and fell further away from surprise leaders Leicester City, before Sunday’s 2-0 win over Bournemouth put them back in contention.
And Nicholas says that there remains a frailty in the side that they do not deliver when it matters, and that is a question that they must answer this season.
“It’s alright saying they’re playing quite nice, but they’ve still got this frailty of not delivering the good when it matters,” he told Soccer Saturday.
“Arsenal will probably finish in the top four, but then that might be the success of their season again.”
“They have to finish teams off with a ruthless belief. They have to prove that side, that’s still the question mark that surrounds my team. Do you have that desire, the clinical attitude to see the points?”
If Arsenal are to be title winners come the end of the season, they will need Olivier Giroud to recapture his earlier season form sooner rather than later.
The Frenchman has been in fine form during this campaign, and is their top goalscorer in all competitions, but recent weeks have seen him fall off and put in some disappointing displays.
The 2-0 win over Bournemouth was another one of those games for him, but with Theo Walcott only having managed three in the league this season, they need him firing once again in the 13 games remaining.