He most recently replaced Aaron Riley against newcomer Pat Audinwood. He defeated Audinwood via guillotine in the first round. He next faced former WEC fighter and UFC newcomer Shane Roller, losing via second-round knockout in a fight reminiscent of Tavares's bout versus Matt Wiman.
He next faced fellow veteran Spencer Fisher in what was considered to be a loser-leaves-town bout. The bout took place in Thiago's native land of Brazil. He defeated Fisher via impressive second-round technical knockout.
Tavares next signed for a big step up in competition against heavy-handed veteran Sam Stout. The bout would again take place in Brazil. Tavares defeated Stout via an extremely close and exciting unanimous decision.
Tavares was next set to face Dennis Hallman but that fight was also cancelled because of personal issues with Hallman's family. Tavares next signed to face Khabib Nurmagomedov in Tavares's native Brazil in January 2013. Tavares suffered a brutal first round knockout loss before then failing the post-fight test for drostonalone and suffering a suspension of nine months, in late January 2013.
In September 2013 Tavares was announced to be returning against Strikeforce veteran and lightweight newcomer Quinn Mulhern. Mulhern was quickly injured and replaced by Justin Salas. Tavares defeated Salas quickly via first round rear-naked choke submission.
After the victory a satisfied Tavares planned to drop to the featherweight division. He signed to make his debut against newcomer Zubair Tuhugov.
- Thiago Tavares vs. Jason Black - Tavares came into the fight undefeated. The fight was the UFC debut of Jason Black.
- Tyson Griffin vs. Thiago Tavares - Tavares came into the fight undefeated.
- Thiago Tavares vs. Michihiro Omigawa
- Matt Wiman vs. Thiago Tavares
- Kurt Pellegrino vs. Thiago Tavares
- Shane Roller vs. Thiago Tavares - The fight was Shane Roller's UFC debut.
- Thiago Tavares vs. Spencer Fisher
- Sam Stout vs. Thiago Tavares
- Khabib Nurmagomedov vs. Thiago Tavares
- Thiago Tavares vs. Clay Guida
- Doo Ho Choi vs. Thiago Tavares