Arsenal played with a mostly settled starting XI in the second half of the season, but there is one position of complete uncertainty. Mikel Arteta found his winning formula as he settled on his attacking trio of Kai Havertz, Leandro Trossard and Bukayo Saka by the end of the season, but there was constant change at left-back for a while. Oleksandr Zinchenko was the undisputed first-choice last season, to the point where Kieran Tierney departed on loan due to a lack of game time. However, injuries and questionable form meant that alternative options were used. Takehiro Tomiyasu spent most of th…