Saturday afternoon, former Atlanta Hawks All-Star center Al Horford verbally agreed to a four-year, $113 million contract with the Boston Celtics.

Despite Atlanta's agreement to bring in Dwight Howard and a competitive offer from the Hawks, Horford said goodbye to the only team he's ever played for and the franchise that drafted him nine years ago.

Celtic Pride!!!!!! 🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀🍀

— Al Horford (@Al_Horford) July 2, 2016

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While basketball reasons certainly played a factor in his decision, a report published hours later via The Boston Globe revealed that the passionate Boston fans and "empty seats" in Atlanta, even "when they were winning", were reasons why Horford made his decision.

"There wasn't as much motivation for him when he saw all the empty seats when they were winning," Tito Horford said. "He said to me, 'Dad, when we were playing Boston, they were down 15 points and they were cheering their team like they were winning the game. They're so into the game.' This is special for us, especially for him."

Tito Horford, a center who played for the Bucks from 1988-90, tried out for the Celtics in 1995. He said he was always impressed by the franchise's rich tradition and unending support.

"Ever since Boston, Danny Ainge and the whole organization began to show interest in him, that opened his eyes," Tito Horford said. "He always had a good feel about Boston."

"Empty seats" may be an understatement when describing Hawks home games at Philips Arena recently.

During the 2015-16 season, the Hawks ranked 22nd out of 30 teams in the NBA in average attendance per game (16,832) and 23rd in percentage of arena seats sold (89.9%).