The 23-year-old Argentine midfielder suffered the setback during Leverkusen's 2–0 victory over Freiburg on Sunday, twisting his left knee awkwardly in the 67th minute before being replaced by Robert Andrich.
Club officials have confirmed that Fernandez will not require surgery and will instead undergo rehabilitation at the team's training base in Leverkusen.
"Speedy recovery Equi!" the club posted on social media, reflecting the disappointment among players and supporters. Fernandez has been one of the key figures in Kasper Hjulmand's midfield since the Danish coach took charge in September following Erik ten Hag's sudden departure.
This marks the second major midfield setback for Leverkusen this season. Exequiel Palacios, Fernandez's compatriot and midfield partner, has been ruled out for the remainder of 2025 with an adductor tendon injury suffered in September.
The absence of both Argentines leaves Leverkusen short of depth in the middle of the park.
Andrich impressed after stepping in against Freiburg and is expected to form a partnership with Aleix García, whose composure and passing have earned praise from Hjulmand.
Malik Tillman's return from a minor thigh strain could offer additional options, though the American's versatility may see him deployed in wider positions. Veteran Jonas Hofmann may also feature in a deeper role if Hjulmand opts for experience to steady the side.
Leverkusen, who went unbeaten in their title-winning 2023/24 campaign, now face one of their toughest tests yet. With two key midfielders out, Hjulmand's ability to adapt will be crucial as the side aim to mount a serious challenge for the Bundesliga crown against defending champions Bayern Munich.
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