In 24 hours, Kendrick Lamar changed the entire conversation in the rap world. Before K-Dot ominously released the cover art for what became the release of "The Heart Part 4," folks were still glowed tf up off of Drake's More Life. It's legit gone from "is Kendrick announcing his album" to "the Beyhive is clapping at Kendrick for his use of the number four" to "oh wait, 'The Heart Part 4' is fire" to "oh, wait, is Kendrick going at Big Sean, though?!" What a time to be a rap fan.

Over the last few years, healthy competition between the most relevant rappers in today's conversation has turned into something more vicious. With no names being thrust into Sean or Kendrick's bars, we can only look at they ways they've operated and the subtle lines they've previously committed to tape. Where did this bad blood between Detroit's finest and Compton's own come from? It's tough to say, but even Ray Charles can see that something is awry. Here's a look at their relationship.

Aug. 13, 2013: Big Sean releases "Control (HOF)"

On the evening of Aug. 13, 2013, anyone who hadn't been paying attention to who was truly in the conversation got a stiff wake-up call thanks to Kendrick Lamar, who ran though this No I.D.-produced cut like a hurricane. Not only did he wash Big Sean on his own shit, he took it a step further and called out everyone who moved the needle, putting them on proper notice.

I'm usually homeboys with the same niggas I'm rhyming with
But this is hip-hop
And them niggas should know what time it is
And that goes for Jermaine Cole, Big K.R.I.T., Wale
Pusha T, Meek Millz, ASAP Rocky, Drake
Big Sean, Jay Electron', Tyler, Mac Miller
I got love for you all, but I'm tryna murder you niggas
Tryna make sure your core fans never heard of you niggas
They don't wanna hear not one more noun or verb from you niggas

​With the fury in Kendrick's voice, you knew he was serious, and to call out the two guys on the song he's with—including the guy who had it set to drop on his album a few weeks later? There's a reason why we called it the best rap verse of 2013.

Aug. 14, 2013: Big Sean speaks on Kendrick's "Control" verse

The next day, the one question people had for Big Sean was, "But did you HEAR Kendrick's verse before you released 'Control'?" Of course he did. "I had my verse on there first," he told Vibe in an interview. "I sent it to Kendrick, Jay Elec, too. And then Kendrick sent that verse back... so when I heard it I was kind of just like cracking up. I was like, 'Alright, that's what it need to get back to, it need to get back to hip-hop, that culture.'"

"Kendrick is my homie," he continued. "We all homies, but it's all sport.... When I heard his verse I wasn’t about to go back and change my verse, that’s cheating. I could [go back and] name drop.... I could cut his verse up, but that ain’t the way of an O.G. That ain’t how G’s move.... If three people hop on a song, someone's gonna have a standout verse always, whether it's 'All Me,' whether it's 'Clique,' whether it's 'Control'."

Aug. 27, 2013: Big Sean releases Hall of Fame, and "Control" isn't on it

Sean prefaced the release of "Control" by saying it didn't make the album "cuz of the sample." Still, fans felt some type of way when it wasn't included on Hall of Fame, since it was THE talk of the rap community some two-weeks before the album's release.

Jan. 26, 2015: Big Sean says there's a lot of "negativity" on "Control"

Roughly a year and some change after "Control" changed the landscape, Big Sean sat down with Complex to talk about the song and the conversation surrounding it. Discussing the sample issues that were previously cited as the reason it didn't make the album, Sean elaborated: "Looking back on it, it was a different vibe than my album. There’s a lot of negativity on that song, and I don’t fuck with negative shit. People love drama, people love bullshit. I knew when Kendrick did that name-dropping that it was just gonna set it off, and I could see why people gravitated towards that verse for that reason. I respected him for thinking of that. I never wanna shade anybody. I would’ve been a ho-ass nigga if I cut that out of his verse, or if I didn’t put the song out." Hmm.

Feb. 24, 2015: Big Sean drops "Me, Myself, and I" freestyle, with subs at Kendrick

When Big Sean jumped on Beyoncé's "Me, Myself, and I" instrumental, these lines jumped out:

Rappers who was killin shit, lately I can't feel that shit
Y'all used to didn't feel my shit and now y'all like, "You hear this shit?"

Speaking with MTV, Sean said that the lines were actually aimed at the "people": "It wasn't even a dis to no rappers, it was a dis to the people," he said. "I feel like people get a little fuzzy-minded and brainwashed when it comes to, like, drama, or, 'He said this!' And they focus on one little part, or the skits. And that ain't it to me."

July 22, 2016: Big Sean and Kendrick Lamar appear on DJ Khaled's "Holy Key"

DJ Khaled is a known anthem-curator and positive force within the rap game, and so it's interesting that on the Major Key track "Holy Key," there's a pair of bars in Sean's verse with a similar flow to Kendrick that could also be seen as callbacks to the "Control" verse.

Woah, I hear a little bit of me in all your favorite rappers
You know it's true, bitch I need respect due

Just saying.

Oct. 31, 2016: Big Sean subs Kendrick on "No More Interviews"

On a track that found Big Sean addressing everything from his past relationship with Naya Rivera to his issues with Kid Cudi, it's hard to imagine that these lines aren't subliminals at his unresolved issues with Kendrick.

And I can’t lie like I like this shit like I usually do
And I’m just not impressed by you niggas rapping fast
Who sound like one big asthma attack but trash when I’m rapping it back
Who you put in your top five and claim they the savior of rap

Kendrick has been deemed the "savior of rap" on numerous occasions, but he's know for his rapid-fire double-time flow. If this isn't about Kendrick, who is it aimed at?

Feb. 9, 2017: Big Sean says Kendrick Lamar didn't wash him on "Control"

On the press run for I Decided, Big Sean stopped by The Breakfast Club to talk shop. When the conversation turned to Sean talking about not disrespecting the work he's put in, Charlamagne said that Kendrick "washed" Sean on "Control." Big Sean defended himself, saying, "No, he didn’t. Stop it, stop it, stop it. And, how long ago was that? What year was that? And I still don’t feel like I got washed, anyway."

As Charlamagne pressed him, Sean took things one step further: "Your opinion. See, that’s what I’m saying, you can’t fuck with some people’s opinions. You know why? ‘Cuz that’s gonna throw you off. You gotta focus on what’s at hand, what you feel in your heart."

Mar. 23, 2017: Kendrick Lamar releases "The Heart Part 4"

With almost three years of perceived subliminals coming Kendrick's way from Sean, it was only a matter of time before Kendrick addressed it, right? Once the public got their hands on "The Heart Part 4," many felt it was clear that Kendrick was gunning for Sean and the darts he's thrown.

My fans can't wait for me to son your punk ass and crush your whole lil shit
I'll Big Pun your punk ass you a scared lil bitch
Tip-toeing around my name nigga you lame
And when I get at you homie don't you just tell me you was just playin
'I was just playing K-Dot, c'mon you know a nigga rock with you, bro'
Shut the fuck up you sound like the last nigga I know
Might end up like the last nigga I know
Oh you don't want to clash? Yeah nigga I know

Again, judging based on what we've heard Sean spit post-"Control," how could Kendrick not have loaded the lyrical chopper and let it fly in Sean's direction—subliminally? The next move is Sean's.

Mar. 30, 2017: Kendrick Lamar releases "Humble"

The second new Kendrick Lamar song in a week contains more lines that fans read as being aimed at Sean. The fact that Kendrick calls his unnamed lyrical opponent "lil'" was read both as a mocking of Big Sean's rap moniker and as a sarcastic nod to Sean's frequent catchphrase, "Lil' bitch." You can read our complete breakdown of the Sean disses (real or imagined) in "Humble" here.