Amir Johnson is ready to defend himself.

After the Sixers beat the Chicago Bulls, 127-108, in their home opener, Johnson tried to get some sleep. In the wee hours of the night, he woke up. He was still recovering from the team's trip to China, and his sleep was irregular, so he started scrolling through Twitter.

"I'm not shy to respond," he said.

And he did.

For all the Philly fans who were complaining about Johnson being on the court, he clapped back with quips such as,  "Jeeish, I'm glad you not GM," and when one fan asked why Johnson was on the team he responded, "They paid me."

He kept going, thanking those who praised him, conceding when someone was right, and offering some light debate where he thought it was warranted.

"I totally get it," Johnson said. "I understand the city — it's a blue-collar city, and if you miss two shots in a row, they'll boo you; you make a few shots, and they'll love you. I enjoy it, I enjoy interacting with them."

Before Joel Embiid was dunking on kids at the park, before he was the social media darling and the most lovable internet troll of the NBA, Johnson was known for his interaction with fans and his defense (more on that later).

In 2011, he was playing April Fools' jokes on his Twitter followers and challenging fans to late-night video-game battles. In 2012, he was taking part in a zombie walk through the streets of Toronto. In 2013, he was holding Q&A sessions at night on Twitter. He would follow fans back, wish fans happy birthday, and take the criticism.

"I embrace criticism," Johnson said. "I wish I'd had a chance to talk to Michael Jordan after he hit a buzzer-beater or after he beat the Lakers, or after a loss even. I think it's a great way to communicate and understand the fans."

In understanding Sixers fans, Johnson realized they will speak their mind no matter what. So, he figured that they would appreciate the same thing from him.

"Sometimes, the fans don't understand a coverage on film or something that they don't see what I see on a play," he said. " 'Why didn't Amir guard or stop the ball?' It's just the side that fans don't see that I try to explain. Some fans get it, and some don't, and if they want to argue about it, I'm fine with that — lets do it."

So, after the Sixers loss in Detroit on Tuesday, Johnson was back at it.

Johnson takes pride in understanding the intricacies of every defensive scheme. It's how he has maintained a lengthy career.

In 2005, Johnson had just graduated high school and was working out with NBA teams. Seattle Supersonics head coach Nate McMillan changed Johnson's approach.

"He told me that I needed to go to college," Johnson said. "I wanted to be a pro, and I thought I was good, and he said, 'It's not that. You just don't understand the terminology of NBA defense.' My shoulders just dropped, because he was right, I didn't understand any of it, or the reasons behind any of it. I had no rebuttal, I had no clap back."

Johnson spent the next year soaking up everything he could with the Detroit Pistons, including Philadelphia native Rasheed Wallace and four-time defensive player-of-the-year Ben Wallace.

"They really helped me out telling me where to be and why," Johnson said. "Sheed everyday was like, 'Yo Amir, you've got to … talk!' Because I was a quiet kid, and that helped me out — they made me a better defender and a better player."

Defense and communication are keys to Johnson's game, and now he's bringing defense and communication to Twitter. So, if you want to talk about some plays, argue, compliment, or just say hi, @IamAmirJohnson is listening.