Other than the UFC, Paulo Filho has competed in just about every promotion known to man.

Filho will make his World Series of Fighting debut Saturday night at WSOF 2, taking on Dave Branch. This marks his first fight back since announcing his retirement in 2011 due to struggles with substance abuse.

When you say the name Paulo Filho, it likely fails to generate much interest in the minds of MMA fans. However, this is a guy that started his career 16-0, including a submission victory over Chael Sonnen back when they both fought in the WEC.

That was the high-point of his career, and the low came just under a year later.

After forcing Sonnen to tap to an armbar in 2007, Filho was scheduled to defend his WEC title against Sonnen again. This time, he missed weight and wound up on the losing end of a decision – the first “L” of his career.

Filho wasn’t brought over into the UFC when they absorbed that division of the WEC, but he did go on to submit Melvin Manhoef later that year.

From there on, it’s been a struggle – both inside the cage and out. Filho has gone just 6-3-2 in his last 11 pro bouts, including losses to Norman Paraisy, Ronny Markes and Marcos Rogerio de Lima – the latter of which doesn’t even have a Wikipedia page.

Can Filho recover from his struggle with substance abuse and a lengthy layoff to succeed in the WSOF and maybe make his way into the UFC? That’s highly doubtful, but he could be a main star in the rising promotion with the right care and time.