Four-time All-Star post player Al Horford agreed to sign a four-year, $97 million contract with the Sixers on Sunday, sources confirmed.

The power forward/center could make up to $109 million with championship bonuses.

The move came just minutes before Jimmy Butler agreed to a four-year, $142-million deal with the Sixers as part of a sign-and-trade agreement that will send him to the Miami Heat in exchange for Josh Richardson.

No signings can become official until July 6. Until then, NBA teams can’t comment on the moves.

Horford’s signing came after Tobias Harris agreed to re-sign with the Sixers on a five-year deal and Mike Scott signed a two-year deal to stay in Philadelphia. But sharpshooter JJ Redick is leaving -- he agreed to a deal with the Pelicans.

In Horford, the Sixers get a proven post player to start at power forward alongside Joel Embiid. Horford can also play center on nights Embiid sits out. His presence could make the Sixers the team to beat in the Eastern Conference, if not the entire NBA next season, if they find a shooter to replace Redick.

With the addition of Horford, Harris will be able to slide back to small forward, Butler’s position.

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