It's the end of the line for Rocky Balboa, and there ain't gonna be no rematch.

After returning this month as a coach in the box-office heavyweight Creed II, Sylvester Stallone announced Wednesday that he's retiring the character of the Philly boxing phenom for good.

"I just want to thank everyone around the whole wide World for taking the Rocky family into their hearts for over 40 years," Stallone posted on Instagram, proclaiming the end to his participation in the 42-year-old, eight-movie franchise. "It's been my Ultimate privilege to have been able to create and play this meaningful character. Though it breaks my heart, Sadly all things must pass… and end. I love you Kind and generous people, and The most wonderful thing of all, is that ROCKY will never die because he lives on in you …."

In the Instagram video, Stallone throws in the towel on the Italian Stallion alongside Creed II star Michael B. Jordan, adding that he thought he had reached the end of the Rocky road in 2006.

"As I step back, as my story has been told, there's a whole new world that's going to be opening up for the audience, for a new generation … Now you have to carry the mantle," he says, raising Jordan's fist.

An underdog in the 1977 Academy Awards, Rocky won best picture, with seven more films produced over a 42-year span. Decades later, Sly also picked up an Oscar nomination for his supporting role in the first Creed film in 2016. In its first five days in theaters last weekend, Creed II made $55.8 million at the box office, the largest-ever Thanksgiving opening for a live-action film.

>> READ MORE: 'Creed II' review: Rocky's greatest foe returns in sequel that lacks punch

While no plans for future Rocky films had been announced, Philly already remains forever changed by the scrappy gray-sweatsuit-wearing fighter who famously sprinted up 72 stone steps of the Art Museum.

"Any blue-collar city, anyone who had to work and not give up and didn't have the most talent can relate to [the Rocky movies]," Philly boxer Bernard Hopkins told the Inquirer in 2016. "It's about someone who became someone in spite of everything. Like, you don't have to have a Harvard degree to be successful. That's a good quote."

From busloads of tourists who flock to the steps of the museum and the bronze statue of the fist-raising boxer at its base (Stallone bought an identical copy of his effigy last year), to the shot glasses and sweatshirts sporting Rocky's trademark pose, the character and film have become symbols of Philadelphia.

Still, Philadelphia native and writer Joe Queenan has acknowledged that the Rocky series had serious issues with race early on, most notably the absence of black characters beyond antagonists Apollo Creed and Clubber Lang.

"It's not who we all are," Mayor Jim Kenney told the Inquirer in 2016. "It's the underdog story, though, and that's how we like to dress ourselves. I never not watch when it's on."

>> READ MORE: After 40 years, Philly icon Rocky still battling for respect

Stallone thanked his fans once again via Instagram on Thursday.

"Yo, due to the overwhelming and loving response to this wonderful character I just want to say one last final farewell," he wrote. "Thank you again the bottom of our hearts."

Beyond the second Creed film, Stallone has also been in the news this past year over allegations of sexual assault, though the Los Angeles County District Attorney's Office said last month that it would not file charges, citing insufficient evidence.