Just when fans were starting to forget about Big Sean's previous engagement to actress Naya Rivera as he is now dating Best Mistake signer Ariana Grande, Rivera has now reminded them with a particular song.

WATCH: Big Sean Dodges Questions About Ariana Grande, Talks Rumors Naya Rivera Used Him 'Didn't Work Out'

Big Sean and Rivera got engaged in October 2013 after dating for about six months. But just weeks later, they shocked fans when they had an ugly split and social media battle back in January 2014. Shortly after, she secretly wed fellow actor Ryan Dorsey and Big Sean moved on with Grande.

Now, Rivera (who plays Santana) joins her classmates and co-stars as they sing Grande and Big Sean's collaboration Problem for the season 6 opener of Fox's hit series Glee.

WATCH: Big Sean On Keeping Relationship Private 'For Me To Know & You To Find Out'

In the teaser Rivera sings, "Head in the clouds got no weight on my shoulder....I should be wiser and realize that I've got..." before rapping Iggy Azalea's feature, "Money betting I'll be better off without you. In no time I'll be forgetting all about you..."

This isn't the first time the former couple was speculated to diss one another through song. Big Sean's newest hit I Don't F With You was rumored to be about Rivera. While he said that he actually wrote the lyrics while the two were still dating, he admitted he went back and added more after they split.

Fans caught wind of Rivera's performance of Problem and took to Twitter to dish on it.

"The irony of Santana on 'Glee' a.k.a. Naya Rivera singing One Less Problem by Ariana Grande, Big Sean's new girl friend...It's unbearable".

Another fan even suggested that Rivera sung the song better than Grande!

They tweeted, "When Naya Rivera sings 'Problem' better than Ariana Grande".

"I'm a lil bit speechless right now..But @NayaRivera gosh you slated in the Problem' performance...The rap part..I wasn't ready wow".

Another added, "Nothing is more awkward than Naya Rivera singing Problem'".

As another wrote, "The fact that Naya Rivra (big sean's ex) sang Ariana Grande (big sean's girlfriend) on glee makes me laugh".

Check out the video below.