Trailblazers stars Damian Lillard and CJ McCollum took the ultimate low road and clowned THE HELL out of the Clippers for their early playoff exit ... and it's saaavaagggeeee!!!

In case you weren't aware ... Lillard and McCollum have big beef with the Clips -- and it all stems from a non-playoff bubble game back in early August.

During the Portland-L.A. matchup ... Lillard wasn't his usual clutch self -- and Clips star Patrick Beverley let him hear it -- chirping and laughing at the guard as L.A. won the game.

Afterward, Lillard, Beverly and Paul George all got into a spat on social media ... with Beverly and George believing at the time Lillard wasn't going to make the playoffs.

In one of Beverly's comments toward Lillard ... the Clippers guard said "Cancun on 3" -- insinuating Damian would be off to Mexico instead of chasing a world title.

Turns out, Lillard and McCollum DID get into the playoffs ... and despite losing in the 1st round to the Lakers -- they never forgot the smack talk, and returned the favor BIG TIME after L.A. was shockingly bounced by the Denver Nuggets in the conference semi-finals Tuesday.

"I guess I should extend this Cancun invite since I haven’t made my arrangements yet," Lillard shot at Beverly.

"I’ll bring the wine," McCollum added. "Weather nice as ever too."

McCollum continued, "My last tweet before I finish this glass. They did vote they ain’t wanna play no more. . . But I didn’t think they was gonna go out like that."