Back in December 2014, Kendrick Lamar became the last musical guest on The Colbert Report. “No pressure,” the eponymous host told the rapper, “but keep in mind that Paul McCartney, REM, Jack White and Nas were your opening acts.” Kendrick laughed along politely, his renowned humility in interviews still very much intact.

Kendrick went on to own 2015, his third studio album ‘To Pimp A Butterfly’ deservedly dominating headphones, playlists and end-of-year lists. But instead of previewing a song from that lauded record on The Colbert Report, the 28-year-old took the option instead to debut a track that’s still to be released. Rather than being a cast-off demo from the TPAB sessions, ‘Untitled’, with its sublime fusion of g-funk and soul with incisive, character-driven bars, was a tongue-wagging exercise in how Kendrick is possibly the most switched-on musician operating right now. Needless to say, the internet was stunned.

This brings us nicely to the rapper’s appearance last night on US chat show The Tonight Show with Jimmy Fallon. Another polite interview (covering subjects such as the great influence of his parents’ music tastes and a nostalgic fondness for vintage video games) was all preamble for the main event, where all eyes would be on Kendrick taking to the mic. Would he perform a TPAB medley, like he did last year on Colbert’s new home at Late Show?

“Performing ‘Untitled 2’, Kendrick Lamar!” announced Fallon, a phrase that made every hip-hop fan desperately scramble to crank up the volume on their speakers. Backed by the Wesley Theory band that he’ll no doubt be bringing along to his slot supporting Florence + The Machine in Hyde Park this summer (and fingers crossed for further headline shows over here in the UK after that), Kendrick launched into yet another unreleased song and, once again, destroyed the stage.

http://www.youtube.com/watch?v=iZJXvjeWlVA

As the Wesley Theory lay down an inescapably groove-tinged funk, Kendrick delivers an opening verse that’s as shrewdly witty as we’ve come to expect from the Compton native: “Why you hate to work for it? / Went to work for it / See a nine to five was so jive turkey / But when Thanksgiving came, checks didn’t hurt me”. Even though it’s mostly recycled material – he debuted much of the verse last year on his new best pal George Clinton’s remix of Funkadelic’s ‘Ain’t That Funking Kinda Hard On You’ – its content still packs a mighty punch.

Elsewhere he invokes TPAB’s first single ‘i’ by reeling off (in character, of course) the things he loves – “I love god, I love speed, I love drank, I love me” – but it’s not without a woah-wait-a-minute caveat: “I love God / But I’m scared of god speed”. The wordplay, as per, is out-of-this-world good, typified by the amount of times that you’ll pause the performance in order to return to a specific part, just to let its message properly soak in. Other nods to the album come with the self-reflecting take down of gangbanging that featured on ‘The Blacker The Berry’ (“We all came on the boat looking for hope / And all you can say is that you’re looking for dope”) and a shout-out to Cape Town – Kendrick’s pre-TPAB trip to South Africa (particularly his visit to Nelson Mandela’s cell on Robben Island) inspired the Afrocentric lyrical approach that guided the likes of ‘Momma’ and ‘Mortal Man’.

All this leads to ‘Untitled 2’’s frenzied ending: with the band raising the tempo, Kendrick matches their intensity by ramping it up to another level entirely, spitting fire on how his label, Top Dawg Entertainment, are “the mafia of the west”, boasting about how he could “put a rapper on life support” (which he readily did on his genre-defining verse on Jay Electronica’s ‘Control” in 2013), and, perhaps most excitingly of all, how he’s on “level two, level two / No I’m not done”. If TPAB was just Kendrick on level one, then Lord knows what kind of heights this exceptionally talented individual can rise to.

“You’ve got the most Grammy nominations for a rapper in a year,” Fallon told his guest prior to this sensational performance. “You’ve already made history.” If he keeps producing the likes of ‘Untitled 2’, then it’s fair to say that Kendrick Lamar is in firm control of the history-writing pen.