BOSTON (CBS) — The Celtics didn’t lose Gordon Hayward for nothing after all.

The Celtics and Hornets officially completed a sign-and-trade deal for Gordon Hayward on Sunday, with the star forward heading to Charlotte on a four-year, $120 million deal.

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The Celtics sent two future second-round picks to Charlotte in the deal, with a heavily protected second-round pick from Charlotte returning to Boston if the Hornets finish in the top five of the NBA next year, according to The Associated Press.

But the real return for Boston comes in the form of a trade exception. According to ESPN and The Boston Globe, the exception is for approximately $28.5 million — the largest trade exception in league history.

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That trade exception can be used to acquire a player via trade, and it remains valid for a year. It can be used on multiple players, too, meaning the Celtics could either add one big-money player or several players at lesser salaries. Danny Ainge could utilize that exception immediately or wait until free agency in 2021.

Hayward ranks among the biggest free-agent signings in Celtics history, so his opt-out and departure figured to dent Ainge’s ability to field a contending roster in the coming years. But the acquisition of the trade exception should allow for some much-needed flexibility and options.

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NBA action is set to get underway soon, with testing beginning this coming week. The preseason will tip off on Dec. 11.