​What is Ajax’s best centre-back partnership?Aaron Bouwman is quickly developing into one of the best central defenders in the Eredivisie, and if he reaches his full potential, he could even become one of the best centre-backs in the world.Bouwman made his debut for Ajax last season and finished the season with 14 appearances in all competitions. Despite still being inexperienced, Bouwman has been a crucial player for Michel Sánchez since the Spanish head coach took over at Ajax in the summer.So far this season, Bouwman has already made the same number of appearances and has started five games for Ajax in the Eredivisie. Former Ajax manager Frank de Boer recently compared Bouwman to Virgil van Dijk, saying he sees similarities between the Ajax defender and Van Dijk in his younger years.Ajax signed Thilo Kehrer on loan from AS Monaco during the summer transfer window, and the German centre-back will provide Bouwman with competition for his place. However, Bouwman has started in the vast majority of Eredivisie games this season when he has been fit. Bouwman is working to improve defensivelyIn an interview with ESPN, Bouwman revealed what area of his game he is currently working to improve.”On the ball, almost everyone says that my level is high. It is only defending that is sometimes something that needs to improve,” Bouwman explained.”Sometimes it’s the choices and those defensive moments. If I really iron out those little things completely, then I’ll be unstoppable.”Against Atalanta, Bouwman was exceptional on the ball in the first half. He played several line-breaking passes. It is something he does to a very high standard. However, in the second half, he made a few poor passes, which gave Atalanta the chance to attack. During the interview, Bouwman opened up about taking risks in build-up.”I love taking that risk in my game,” Bouwman said.”Sometimes it is, of course, a bit too much, but if it pays off, which often happens, you get something beautiful out of it as a team.”Bouwman talks about signings in central defenceAjax revamped their central defence during the summer. Josip Sutalo departed to Lazio on a loan deal, with the Serie A club holding the option to sign him permanently in the summer. Ko Itakura returned to Borussia Mönchengladbach in the summer. The Japanese defender endured a difficult year at the Johan Cruijff ArenA and struggled for form. Ahmetcan Kaplan also moved to NEC Nijmegen on a permanent transfer, having spent last season on loan there.As already mentioned, Kehrer was one of the players signed to add depth to Ajax’s central defence, particularly on the right side, which is where Bouwman plays. Kehrer has also been used as a right-back at times this season, and it is likely a position the German defender and Michel may opt to use him in more often throughout the season.Ajax also signed Daley Blind, and Dies Janse returned to the club after a productive loan spell at FC Groningen. Both Blind and Janse are left-footed and