The Frenchman scored his 50th Premier League goal at the weekend, netting early in the win over Aston Villa.
It comes hot on the heels of his crucial Champions League hat-trick against Olympiakos in midweek.
Former top flight footballer Crooks told the BBC: "[He] looked majestic throughout. Just why there was even a debate about who should play upfront for Arsenal when Theo Walcott was insisting he should play there, I really can't comprehend.
"There's only one man to lead the line for Arsenal and that is Oliver Giroud."
Giroud is certainly the man in form and a player Arsene Wenger cannot drop right now. But it can't be forgotten that it was not so long ago that Walcott was shining in the same position.
Walcott was instrumental up front in the win over Manchester United, with his speed combining with Alexis Sanchez to tremendous effect.
Arsenal are fortunate they have two credible options, and at present both are fully fit. Giroud's form could further dissuade Arsene Wenger from going back into the transfer market in January.