Eminem Says Kendrick Lamar, J. Cole Fuel His Hunger in Rap Game

Eminem's doing a bit of closet cleaning ... in an extensive and rare interview where he details his past drug use and reveals his biggest influencers currently in the rap game!!!

In a first-person spill with XXL, Eminem admitted he still takes his music seriously these days -- so much so, he has the likes of Kendrick Lamar, J. Cole, Joyner Lucas and Big Sean in his crosshairs ... on a competitive level, of course.

Eminem is the highest-selling rapper of all time, and openly admits chasing numbers and stats doesn't entice him anymore. Instead, he says watching the quartet of younger rappers' every move has become a pastime for the 49-year-old hip hop legend.

He says he's "watching them and how the fuck they're doing their s***, because they're also focused on being the best rappers."

Em continued, "I still love to rap. It's always been the most important thing to me. I still have fun writing. I have fun watching the rappers I just mentioned, and being like, OK, let me see if I can do something that inside I think I can top that. And every time the best rappers drop an album, it changes the landscape of the fuckin' game.

"At least it does for me, and I'm like, I need to be able to rap like that. Because if I don't do that, someone's going to come behind me, probably in the next couple of years, and wash me."

Marshall also chronicled his timeline of drug use, including his near-fatal overdose, and also recalled a time 50 Cent saved his butt on live television when he was too high to even answer questions on 106 & Park!!!

The painful clip is how it looks ... Em says his "wheels started to come off" as he stumbled through the 20-minute interview.

Of course, Slim Shady has been clean for years and is currently swimming in rumors he's prepping to release new music ... in addition to helping Snoop Dogg and Dr. Dre on their upcoming joint album.