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22 years had passed since Ajax's last Champions League semi-final appearance before Frenkie de Jong joined the team. Their previous semi-final appearance was in the 1996-97 season, where they lost to Juventus. De Jong's arrival in the 2019-20 season marked a significant milestone for Ajax, as he played a pivotal role in their run to the semi-finals that year, ending their long absence from the competition's latter stages.