Back in 2016, Spotify partnered with Genius to bring lyrics and backstory to its pop music playlists. Today, however, the musical reference guide has drawn a bit of a line in the sand, partnering with Spotify’s chief competitor.

Genius announced via blog post today that it’s firmly in the Apple Music camp. The new deal brings the service’s lyrics to “thousands of hit songs” via Apple’s desktop and iOS app. In addition to that deal, Genius will also be using Apple Music as its own preferred music player.

That means when you visit Genius’ site or use its iOS app, Apple’s software will be the default for playing back the song you’re viewing.

“Being able to read lyrics and annotations on Genius while you listen along on Apple Music is a dream Genius experience,” Genius CSO Ben Gross said in a statement tied to the news. “We’re proud to make Apple Music our official music player, and we’re doubly excited to bring Genius lyrics to their amazing platform.”

Siding with a competitor is no doubt a bit of a blow for Spotify, which has been struggling to defend marketshare as Apple Music continues to grow. As Sarah noted recently, lyrics and a lack of voice support have been a growing sore spot for the service of late.