The two highlights of Nicolai Rapp's career to date have come with SV Werder Bremen and 1. FC Union Berlin, having secured promotion to the Bundesliga with both clubs. While Union needed a tense play-off victory over VfB Stuttgart in 2019, the Green-Whites finally secured direct promotion in 2022 in a meeting with Jahn Regensburg. “They were two very special moments,” said Rapp. “The play-off with Union was even closer. When the final whistle was blown, it was just amazing.”