The Scottish left-back has been getting used to life at The Emirates after having signed for the Gunners from Celtic in the summer transfer window.
Tierney has been recovering from an injury he picked up before his move to Arsenal but he is now back in full training and is waiting to make his Premier League debut for the Gunners.
The 22-year-old has so far made two appearances for Arsenal so far this season and he will be hoping to be involved when the Gunners travel to Bramall Lane on Monday night.
And Emery has revealed that Tierney is now fully fit and ready to compete for a starting spot in the line-up against the Blades.
Speaking at his news conference on Thursday, Emery said: “[Tierney is] ready to play.
“Now we have two options in that left-back role with Sead Kolasinac and him. We’re going to play a lot of matches after Monday. We will need every player.
“It depends how he comes into the first training with us, Sead, after his international matches.
“We now have two players in that position and we can use one on Monday, it depends how they are, one or the other.”
Emery also revealed that he will make a late decision on whether to start Alexandre Lacazette for Monday’s trip to Sheffield United.
The French striker has been out of action with an ankle injury but he has returned to full training and is on course to return to action.
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