Kevin Garnett, Paul PierceFor Paul Pierce, being a Celtic was the NBA equivalent of his first love. He will never forget the feelings he had, and he feels a tinge of regret saying goodbye.

Pierce wore his emotions on his sleeve during his introductory news conference with the Brooklyn Nets on Thursday, expressing excitement for the coming season while exhibiting obvious disappointment over leaving the only home he’s ever known as a professional basketball player. His first trip back to TD Garden should be an emotional experience, as he has gone over the moment again and again in his mind.

Each time Pierce imagines himself taking to the parquet as a visiting player, his reaction is the same.

“I know it’s going to be real emotional,” Pierce told reporters. “I’ve already pictured it in my head a hundred times, and every time I’ve pictured it, I’ve shed tears. That’s going to be difficult, man. It’s going to be difficult. It’s like the first girl you were in love with. You cried and thought about her, probably sent her letters. She rejected you and you cried some more. Then you moved on.”

Pierce was speaking hypothetically, but it’s clear he is no stranger to getting dumped. The biggest difference in this case is that even though the Celtics sent him packing, their fans will still welcome back with open arms any time he returns.