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Arsenal are reportedly planning to make a move for Borussia Dortmund striker Pierre-Emerick Aubameyang if Alexis Sanchez departs the Emirates Stadium during the January transfer window.

According to Sky Sport Italia (via Football Italia), the Gabon forward will become a key target to replace Sanchez should the former Barcelona man move to Manchester City:

Sanchez, 29, has only six months remaining on his Arsenal deal and was heavily linked with a move to City last summer.

Sky Blues manager Pep Guardiola seemed to effectively rule out a January move for the Chilean recently when he said he believed Sanchez would remain at Arsenal during the winter transfer window, per MailOnline's Jack Bezants.

That does not mean Sanchez will not eventually leave Arsenal for City when his deal expires at the end of the season, though, in which case the Gunners need to find an adequate replacement.

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Along with Mesut Ozil—who is also out of contract in the summer—Sanchez has been Arsenal's key attacking presence since he joined the club in 2014.

Arsenal will need to bring in a top-quality forward to replace him, and Aubameyang could be an ideal target.

The 28-year-old has been hugely prolific in the Bundesliga during the last three seasons, netting 69 goals in 78 appearances while also thriving in European competition.

He is also reportedly available as his relationship with Dortmund's hierarchy has broken down recently, per Darren Lewis of the Mirror.

BVB are unlikely to let Aubameyang go cheaply as he is a valuable asset and has a contract with the club to 2021.

However, it is inevitable Arsenal are going to have to splash out in order to properly replace Sanchez, and Aubameyang could be a brilliant capture given his effectiveness in front of goal.