In 1989–90 United finished two places lower in the league in 13th. Leighton played when United were defeated 5–1 in the league by newly promoted neighbours Manchester City, and conceded three goals in 1990 FA Cup Final, a 3–3 draw with Crystal Palace. He was then dropped from the United starting lineup for the replay, in which Les Sealey made a number of saves as United won the match 1–0. Leighton's disappointment was such that when handed the winner's medal by Sealey, he later returned it to his replacement's pocket, and when a medal specifically for Leighton was received by the club due to his appearance in the first match, he declined that too. The two players remained close friends, although Leighton's relationship with Ferguson deteriorated to the point where the two were no longer on speaking terms.