Arsenal have conceded 50 goals this season in the Premier League, one less than last season with one game left to play. Shkodran Mustafi has been under most criticism this season. It seems likely that Unai Emery will make changes to the Arsenal's defence. How can Unai Emery solve Arsenal's problem in one transfer window?

The Left-Back Position

Despite having Sead Kolasinac and Nacho Monreal, Arsenal will have to make slight changes to the left-back position. Kolasinac has proved himself useful, offensively, and Monreal has been mostly used as a Centre-Back this season. Arsenal need to bring in someone who can provide his services as a left-back, offensively and defensively.

The Ajax and Argentine star, Nicolas Tagliafico, has been linked with a move away from Ajax. Nicolas has been crucial to Ajax's journey in the Champions League and the Eredivise, this season. In his 3831 minutes played this season, he has provided 6 assists and scored 5 goals in all competitions. According to transfermarkt, Nicolas Tagliafico could cost Arsenal £22.5m.

The Scottish and Celtic youngster, Kieran Tierney, is another option for the Gunners. Kieran Tierney has been linked with Arsenal for quite some time now. In his 3429 minutes played this season, he has provied 5 assists and 1 goal in all competitions. He is valued at a bargain price of £11.25m.

Centre-Back Problems

Despite having veteran CBs such as Laurent Koscielny and Sokratis Papastathopoulos, Arsenal have not had the best season, defensively. With Shkodran Mustafi likely to leave the club this summer for a price nearing $20m, Arsenal could use that money and the budget to bring in a World-Class CB.

Samuel Umtiti has been heavily linked with Arsenal this season. In the 2018/2019 season, Umtiti has not been used by Ernesto Valverde that much. Due to that, the French defender has become unsettled and is very likely to move away from Barcelona this summer. Unai Emery has been thinking of adding to Umtiti to his squad before the start of the 2019/2020 season. He could cost the Gunners a whopping $63m. According to Arsenal fans, despite the high price, he could be a quality addition to the squad.

The Greek Roma Centre-Back, Kostas Manolas, is another player Arsenal could look into. He has proved vital for Roma ever since his signing in 2014. He could link with his international teammate, Sokratis. The Greek defender could cost Arsenal only $36m which is to be paid in installments.

At the moment, it seems very likely that Maitland Niles and Hector Bellerin will be fighting for their right-back position next season. Both of them are outstanding players and could prove vital for Arsenal. Therefore, bringing in another player in that position could unsettle one of them as playing time issues would arise. Arsenal could, however, look into a younger right-back player such as Achraf Hakimi.