Mayweather extended his unbeaten record to 44-0 after outclassing Guerrero with a unanimous 117-111 score.
Speaking after the fight, the welterweight said that an injury early on forced him to adopt tactics that were not originally in the plan for the fight.
"I hurt my right hand midway through the fight so I couldn't go for the knockout the way I wanted. I had to box smart," Mayweather told reporters.
"I still tried to get him out but the knock out I wanted for my fans didn't happen.
"I was happy to have my father back in my corner. I got hit too often in my last fight against Miguel Cotto and my father took me back to using my defensive skills. I'm 36 now and I must hold on to those skills from now on."
The victory was Mayweather's first fight since beating Cotto on May 6 last year.