The NBA's rich has gotten richer. Free agent shooting guard Ray Allen has spurned a contract offer to return to the Boston Celtics and chosen to join the defending NBA champion Miami Heat. Contract details have not yet been released, but it's widely believed that the Heat offered Allen the "mini-mid level" exception, which is worth $3 million a year.

As is fitting for 2012, the news was first broken on Twitter by Heat owner Mickey Arison.

Its 2:30am in London and I was just woken up with great news.Welcome to the family #20!!

— Micky Arison (@MickyArison) July 7, 2012

It has been said that Allen has been holding a grudge against the Boston front office over various incidents that occurred last season, including his benching in favor of Avery Bradley and nearly being traded to the Memphis Grizzlies. Yahoo's Adrian Wojnarowski had sources on Friday night that at least confirmed the latter.

Allen will likely join Miami's unorthodox rotation, alongside Shane Battier and Mike Miller, as an almost exclusive three-point shooter.

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