Arsenal are seemingly taking more of a proactive approach to this summer’s transfer window than they did during 2015. While goalkeeper Petr Cech was the only first team player to be signed last summer, the Gunners have already added £30 million central midfielder Granit Xhaka, and it’s not even June yet. The addition of Xhaka will certainly boost the club in the middle of the pitch in a multitude of ways.  However this shouldn’t and most likely won’t be the north London club’s last piece of business of the summer.

With the midfield shored up for the near future, Arsenal now need to add both a top-class center forward and a central defender.  Striker Danny Welbeck will be missed for about half of the 2016/17 season due to a significant injury and the Gunners cannot rely on Olivier Giroud alone up front for a majority of the season.  On the defensive side of things, Laurent Koscielny is widely regarded as one of the top center backs in the Premier League.  Things, however, get a bit murky alongside the Frenchman’s partner in crime.

Per Mertesacker is 31 and entering the final year of his current contract.  Normally among the team’s first-choice central defenders, the BFG’s level of play has dropped in recent memory.  Speed has never been Mertesacker’s strong point. However,  the German has appeared to lose a further step over the last calendar year and even lost his starting place to Gabriel Paulista during the 2015/16 season.

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Gabriel began his Arsenal career very promisingly.  The Brazilian oozes grit and passion, something that this Arsenal team has desperately needed, but he has also been prone to mistakes at the back as well.  His partnership with Koscielny during the 2015/16 season wasn’t stable and it looks as if the Gunners need to bring an additional center back in to better compliment Koscielny’s playing style.

Napoli’s Kalidou Koulibaly is the latest central defender to be linked with a move to Arsenal. The Senegal international is an absolute rock in defense for Napoli. Koulibaly possesses a fantastic combination of pace and strength, and would be a solid long-term replacement for Mertesacker.  Reportedly valued at about £20 million, the Gunners could potentially get an exceptional, experienced center back for just a few extra million pounds than they paid Southampton for Calum Chambers.

Rumors have also surfaced that Medhi Benatia could be a target for the Gunners. Benatia, now 29, has struggled to remain in Bayern Munich’s starting XI.  Mainly due to injuries, the Moroccan international has managed just 24 Bundesliga starts since joining the German giants in 2014.  While Benatia has struggled with injuries over the last couple of seasons, there’s no doubting his talents when he is on the pitch.  The well-rounded former Roma player would be a welcome addition to the Gunners squad, and with Mats Hummels being brought into Bayern, there may not be room for Benatia in Bavaria.

Finally, while there may not be any reports linking him to Arsenal, Southampton’s Virgil van Dijk should be another center back the Gunners should consider adding to their squad.  The Netherlands international has been a smash hit since arriving on the south coast last summer, and would fit seamlessly into the Arsenal starting XI.  The north London club have looked inept at defending balls in the air lately, and van Dijk’s best attribute is his aerial abilities.

Most Gunner fans would be thrilled if any of the three aforementioned defenders were to ply their trade at the Emirates next season.  Each of the three players have their specific strengths (and weaknesses), but all would be worthy of a starting position next to Koscielny. If the Arsenal brass can secure one of these defenders, there would seemingly only be one piece of the puzzle left to buy this summer: a center forward.