The 2021 J.League Cup, known as the 2021 J.League YBC Levain Cup () for sponsorship reasons, was the 29th edition of J.League Cup, a Japanese association football cup competition. It began on 2 March 2021 and ended on 30 October that year.
FC Tokyo were the cup holders, having won their third title. They failed to defend their title after being eliminated by eventual winners Nagoya Grampus in the semi-finals. Nagoya Grampus won their first ever J.League Cup title, defeating one-time winners Cerezo Osaka in the final.
All 20 teams playing in the 2021 J1 League participated. Four clubs involved in the 2021 AFC Champions League received byes for the group and playoff stages: Kawasaki Frontale, Gamba Osaka, Nagoya Grampus, and Cerezo Osaka.
Sixteen teams played in the group stage. They were divided into four groups of four teams by their finish on the 2020 J1 and J2 Leagues (parenthesized below).
Each group were played on a home-and-away round-robin basis. Each match were played in 90 minutes.
All times listed are in Japan Standard Time (JST, ).
In the group stage, teams in a group were ranked by points (3 points for a win, 1 point for a draw, 0 points for a loss). If the points were tied, the following tiebreakers were applied accordingly:
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The play-off stage was played as two-legged ties of two teams each. The away goals rule, an extra time (away goals rule not applied for the scores in the extra time), and a penalty shoot-out would have been used if needed.
The play-off stage was held over two legs; on 2, 5, and 6 June 2021 (first), and 6 and 13 June 2021 (second). All times listed are in Japan Standard Time (JST, ).
Kashima Antlers won 3âÂÂ1 on aggregate.
FC Tokyo won 4âÂÂ2 on aggregate.
Consadole Sapporo won 4âÂÂ2 on aggregate.
Urawa Red Diamonds won 4âÂÂ3 on aggregate.
The prime stage (knockout stage) was played between four teams which won at the play-off stage and the four 2021 AFC Champions League participants entering the tournament at this stage. The prime stage was played as two-legged ties of two teams each. The away goals rule, an extra time (away goals rule not applied for the scores in the extra time), and a penalty shoot-out were used if needed.
The quarter-finals and the semi-finals were played as two-legged ties (same as the play-off stage). The final was played as a single game.
The quarter-finals were held over two legs; on 1 (first) and 5 September 2021 (second). All times listed are in Japan Standard Time (JST, ).
FC Tokyo won 3âÂÂ2 on aggregate.
Nagoya Grampus won 4âÂÂ0 on aggregate.
Cerezo Osaka won 4âÂÂ1 on aggregate.
4âÂÂ4 on aggregate. Urawa Red Diamonds won on away goals.
The semi-finals were held over two legs; on 6 (first) and 10 October 2021 (second). All times listed are in Japan Standard Time (JST, ).
Nagoya Grampus won 4âÂÂ3 on aggregate.
Cerezo Osaka won 2âÂÂ1 on aggregate.