Drake Admits 'Too Good' Is About Serena Williams in BTS Studio Footage

Drake has just confirmed a long-suspected theory about one of his hit songs ... as the rapper has dropped never-before-seen footage from the studio.

The hitmaker released a bunch of archival footage from the last several years ... including one telling video, where he makes a big confession about his 2016 anthem, "Too Good," featuring Rihanna.

Watch the vid ... as Drake dishes to his mother -- who is off camera -- that he wrote the song with former flame Serena Williams in mind.

As his mom questions the intention of the song -- as it's about being "too good" for a lover -- Drake defends he's making the track both about the tennis champ ... and for her.

He adds ... "If I'm gonna talk about [women], I'll at least do them the justice of making them a song that they like. So, I know Serena very well and I know that she'll hear it loud and clear."

Per Drake, he doesn't think Serena will "hate" him for the single ... since it's lighthearted.

Drake's mom appears to needle her son a bit during the conversation, reminding him that Serena has already moved on to someone else ... likely referring to SW's relationship with future husband Alexis Ohanian, who she began dating in 2015.

TMZ broke the story ... longtime friends Serena and Drake were confirmed to be a couple after they were caught locking lips in a Cincinnati restaurant. They quickly became inseparable, attending everything from New York Fashion Week to restaurant openings.

However, they burned out as quickly as they heated up ... as Serena found herself engaged to Alexis by the end of 2016.