In all, manager Arsene Wenger makes three changes to his starting XI following the 4-0 humiliation at Liverpool before the international break.
The Gunners boss admitted that Sanchez was struggling mentally following his exploits with Chile over the last fortnight, which saw him come in for criticism in his homeland after two crushing World Cup qualifying defeats.
Fellow summer arrival Sead Kolasinac also earns a recall following Alex Oxlade-Chamberlain's departure for the Reds, with Hector Bellerin, Aaron Ramsey and Granit Xhaka retaining their places in the midfield.
Despite speculation that he might switch formation, Wenger has stuck with three at the back and swapped out Rob Holding for Shkodran Mustafi on the right of the defence. Laurent Koscielny starts despite picking up a knock during his exploits with France, while Nacho Monreal is at left-back and Petr Cech is between the posts.
Eddie Howe makes one change for the Cherries and switches to an expected 3-4-3 formation as he looks to bounce back from the late 2-1 defeat to Manchester City last time out.
Adam Smith is expected to play further forward on the right of a midfield that also includes Dan Gosling, Harry Arter and Charlie Daniels, while Steve Cook, Nathan Ake and Tyrone Mings are in defence ahead of Asmir Begovic in goal.
Elsewhere, captain Simon Francis is named among the substitutes after overcoming a hamstring injury.
Arsenal: Cech; Mustafi, Koscielny, Monreal; Bellerin, Ramsey, Xhaka, Kolasinac; Ozil, Welbeck; Lacazette
Subs: Ospina, Mertesacker, Coquelin, Iwobi, Walcott, Sanchez, Giroud
Bournemouth: Begovic; S Cook, Ake, Mings; A Smith, Gosling, Arter, Daniels; King, Defoe, Fraser
Subs: Boruc, Francis, Surman, L Cook, Pugh, Ibe, Mousset
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