He was pretending.... He just wanted to lose the title so he can work on his acting career.
Even though he had all these other options.
1. Retire with the belt and undefeated and the best legacy in the sport of MMA.
- Come back if he ever feels the itch to fight again.
2. Ask Dana to create an Interm belt so he can take some time off.
3. Forfeit the belt so he can look for those interesting fights people are talking about.
Alot of options better then getting a concussion and putting a black mark on your legacy so you can not have the belt and focus on acting.
But nope.... Anderson lost on purpose.