Read this next sentence carefully: Chris Brown will collaborate with Rihanna for a remix of her track "Birthday Cake." Uh huh, one more time: Chris and Rihanna, awful domestic abuse history and all, will work together again.

That's awkward to begin with, but let's also reflect on the lyrics to the original version of "Birthday Cake". Take the lyric, "Just get up on my body, I'll do anything," for example. Or the line "I'mma make you my b*tch." Ughh, this is gonna be weird.

Inspired by the weirdness of this "Birthday Cake" collab, we put together a list of other musical collaborations that aren't exactly a natural fit. The oil and water of musical collaborations, this week's Playlistin' is all about awkward duets.

7. Nelly and Tim McGraw - "Over and Over"



The country star and the rapper join forces for an adult contemporary hit for the ages. I've gotta admit, the song actually worked out a lot better in reality than it did on paper.

6. Ozzy Osborne and Miss Piggy - "Born To Be Wild"



One of the meanest rockers of all-time gets together with arguably the meanest muppet of all time, which actually kind of works. Kermit's time spent on set was probably more awkward than the entire song.

5. Michael Bolton + Lady Gaga - "Murder My Heart"



"Murder My Heart" was originally written by Gaga, who also contributed vocals to the chorus for Michael Bolton's version. It might not be a full on collaboration, but the presence of the two on one track was good enough to make the list.

4. Celine Dion + R. Kelly - "I'm Your Angel"



You might think two artists as different as these two would have a bit of trouble working together, but apparently great singing pipes is all you really need to make a number one hit.

3. Slash + Fergie - "Beautiful Dangerous"



For "Beautiful Dangerous," Fergie took her pop singing chops to the rock world for a song with legendary guitarist Slash, proving she's more versatile than any of us knew.

2. Willie Nelson & Snoop Dogg - "Superman"



Let's be honest, there probably is one thing you can think of that these two have in common. Aside from that though, we're not sure what originally drew these two legends of the country and rap genres together.

1. Eminem and Elton John - "Stan"



When Elton John announced that he'd be joining Eminem for a performance at the 2001 Grammys it was a bit of a shock. After all, Eminem's lyrics were widely criticized as homophobic. But the performance went off without a hitch and afterwards multiple critics suggested that the public display of friendship the two shared would go a long way towards quelling any homophobia controversy.

Got an awkward duet we forgot? Tell us in the comments.