Jīnwǎn de bǐsài shì liǎng zhī sùdí qiúduì de duìjué.
Tonight's match is a showdown between two longstanding rival teams.
Tips
memory
宿 here means 'long-standing / from the past' (as in 宿愿 'long-cherished wish', 宿命 'predestined fate'), not 'to lodge'. So 宿敌 = an enemy of long standing — not a recent grudge but a deep, history-laden rivalry.
register
Slightly literary, common in news, sports commentary, and fiction. Stronger than 对手 (duìshǒu, opponent) — implies real, often emotional history.