Jeremy Lin has played just one game for the Brooklyn Nets this season. Getty

Remember Jeremy Lin? The combo guard who for a stretch of games in the 2011-12 season dazzled Madison Square Garden during the Linsanity craze? Well, it turns out he's still in the NBA, though it's been a while since he was actually on the court.

The 29-year-old suffered a ruptured patellar tendon in his right knee on the Brooklyn Nets season opener and hasn't played since. Clutching his knee beneath the basket at Bankers Life Fieldhouse in Indianapolis, Lin was seen grimacing and mouthing the words, "I'm done."

While his career may not be done, Lin won't be back anytime soon, as he seems certain to miss the entire season. The patellar tendon is the structure that connects the kneecap (patella) to the shin bone (tibia) and rupturing it requires a minimum of three months to return to normal daily activities and at least six months for competitive sports to be resumed.

“We feel awful that the injury will cost him the season, however our entire organization will be there to support Jeremy in every way possible throughout his recovery,” general manager Sean Marks said in a statement on Oct. 19. “Jeremy remains an important part of this team and will continue to contribute in a leadership role.”

On Nov. 30, Lin posted a video on Instagram that he was rehabbing outside Vancouver.

“The Nets and I have decided on a really comprehensive rehab program that will have me out here for most of the season. The goal is to rebuild my body from the ground up, each and every muscle and joint, not just the patellar tendon. I can't wait to get healthy and come back even stronger," Lin said in the video.

Lin would later return from Canada and on Dec. 17 was seen on the Nets bench for the first time since his injury. But his return to New York may not have lasted long, as he posted a Christmas message this week from downtown Vancouver, suggesting there is still plenty of more work to be done on his knee with his rehab efforts taking place at Fortius Sport & Health in Burnaby, British Columbia.

Recovering from a ruptured patellar tendon can be difficult. Former NBA forward Caron Butler suffered a similar injury in January 2011 and it took him roughly 11 months to fully return to action.

The road back for Butler, whose injury included his kneecap sliding roughly three inches up his thigh because of the tendon tear, involved a great deal of rehab that ultimately paid off. Knowing that his season was lost with the Dallas Mavericks, Butler nonetheless was the first player to begin pregame workouts in June during the 2011 NBA Finals, as he sought to potentially return after a little more than six months.

Butler ultimately didn't play in the title series, but he returned to full action in December 2011, wearing a knee brace during practices and games. Butler's statistics only saw a minor dip and he was able to play five seasons after his injury.