The Celtics weren’t designed to quit like this

In an NBA postseason filled with painful exits, the Boston Celtics are one loss away from leading the league in misery.

That might sound hyperbolic or melodramatic given that Boston is one of the final four teams left standing, and that it is competing in its fifth Eastern Conference finals in the past seven years. Of course, there are plenty of other teams with gnarly wounds, including the Philadelphia 76ers, Milwaukee Bucks and Phoenix Suns, to name three aspiring contenders that quickly fired their accomplished coaches once they were eliminated.

Yet Boston, which trails the Miami Heat 3-0 in the East finals, appears to be an unlikely candidate to become the first team in NBA history to win a playoff series after losing the first three games. If the Celtics can’t buck history, their pain will cut deepest because of how carefully their roster was built, how successful they have been for years and how close they came to winning a title last season.

Boston has followed a sound blueprint by building its nucleus through the draft, making savvy moves to address areas of need and staying patient through playoff shortcomings. Now, with a homegrown core all grown up, the Celtics are suddenly left to wonder if they will ever get to enjoy their long-awaited championship pay off.

The Heat obliterated the Celtics in Sunday’s Game 3, running off a 128102 blowout victory in a game the oddsmakers had expected Boston to win. Though Las Vegas looked foolish in hindsight, its confidence in Boston was understandable. The Celtics, already down 0-2 in the series, were the more desperate

Wilfredo Lee/Associated Press Boston Celtics forward Jayson Tatum reacts during the second half of Game 3 of the NBA Eastern Conference finals against the Miami Heat on Sunday.