Wenger has played Sanchez upfront this season and the Chilean has responded with eight goals so far this season.
Since returning from injury, Giroud has also impressed all front, coming in as a substitute to grab a brace in the 4-1 win at Sunderland on Saturday, October 29 and scoring again in Arsenal’s 3-2 Champions League win at Ludogorets on Tuesday, November 1.
"There is no plan B in any squad, I never thought about my players like that," Wenger said in his press conference ahead of Sunday's north London derby at home to Tottenham.
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"The team who is the most effective for the next game, that's what you pick and I consider everyone as a regular player. That is basically what a manager thinks, what is [best] for the next game.
"If he is involved in the next game in your mind, he plays. If not then he doesn't start. He has shown he is a huge asset for the club and I have always supported him."
Arsenal face Tottenham in the Premier League on Sunday, November 6.