MIAMI — The proposition that could have made the Miami Heat a front-runner in the Eastern Conference seemingly has turned into a worst-case scenario for Erik Spoelstra’s team.

Instead of landing Damian Lillard in the wake of the Portland Trail Blazers All-Star guard requesting a trade to the Heat, the Blazers on Sunday closed the second of two Lillard-related trades that strengthened the Heat’s prime East rivals.

Days after sending Lillard to the Milwaukee Bucks, the Blazers on Sunday reached an agreement to send Jrue Holiday to the Boston Celtics. Holiday had been acquired from the Bucks by the Blazers in the Lillard deal.

A week ago, the Heat appeared the front-runners to field a lineup this coming season featuring Lillard, Jimmy Butler and Bam Adebayo, heightening their chances for a third trip to the NBA Finals in five seasons.

Instead, in going against Lillard’s wishes for a deal to the Heat, Blazers general manager Joe Cronin sent Lillard to the Bucks, followed by Sunday’s Holiday move with the Celtics.

After months of a perception that the best possible deal for Lillard would come from the Heat, the Blazers instead maxed out by winding up with Suns center Deandre Ayton, Suns 2022 second-round pick Toumani Camara, Celtics center Robert Williams, Celtics guard Malcolm Brogdon, the Golden State Warriors’ 2024 first-round pick (top-four protected), the Celtics’ 2029 first-round pick, the Bucks’ 2030 first-round pick and the ability to swap first-round picks with the Bucks in 2028 and ’30. It is possible that the Blazers next flip Brogdon for further capital.

A Heat package for Lillard was centered on guard Tyler Herro and at least two first-round picks. The Heat also had the ability to add another first-round pick, a pair of pick swaps, and players such as Caleb Martin, Haywood Highsmith, Nikola Jovic and Jaime Jaquez Jr.

Even had the Heat offered a large package, it likely would not have surpassed what the Blazers pulled in for Lillard (moves that had Portland also sending out Nassir Little and Keon Johnson to Phoenix).

While Milwaukee and Boston emerged stronger through their dealings with Portland, the moves also came at a cost to both teams. Milwaukee now moves forward without Holiday and guard Grayson Allen, who was sent to the Suns in the Lillard three-way deal. Boston had to part with Williams and Brogdon.

While the Heat defeated the Bucks in last season’s first round of the playoffs and then defeated the Celtics in the Eastern Conference semifinals, both of those teams have been significantly bolstered this offseason.

Milwaukee now is positioned to field a starting lineup Brook Lopez, Giannis Antetokounmpo, Bobby Portis, Khris Middleton and Lillard. Boston now can field a starting lineup of Al Horford, Krsitaps Porzingis, Jayson Tatum, Jaylen Brown and Holiday, having added Porzingis earlier this offseason in a trade with the Washington Wizards.

The Bucks finished first in the East last season at, 58-24, with the Celtics second, at 57-25. The Heat closed seventh in the East, at 44-38, before making their run to the NBA Finals as a No. 8 seed through the play-in round.

The Heat hold their media day Monday at Kaseya Center, before opening training camp Tuesday in Boca Raton at Florida Atlantic University.