The pain from the Celtics’ Game 6 and 7 losses to the Miami Heat in the Eastern Conference finals was revived Thursday night when the Heat finished off the Oklahoma City Thunder in five games to win the NBA championship.

Miami entered the series as the underdog, supposedly unable to harness the athleticism of the Thunder, not talented enough at point guard and center to compete, and too reliant on LeBron James to win.

None of those theories came true, and if you use the associative property, and conclude that if Miami beat Oklahoma City in five games, and Miami needed seven games to beat Boston, then the Celtics are the NBA’s second-best team, despite all their injuries.

The success of the Heat should not discourage the Celtics, but motivate them. Miami will be favored to win the Eastern Conference again next season, and unless management makes some substantial deals, the Heat’s title defense will occur with mostly the same roster.

Signing James, Dwyane Wade, and Chris Bosh reduced roster flexibility, and with each receiving raises for next season, the Heat will remain a luxury-tax team. The club’s biggest offseason news could come from Mike Miller, Thursday’s Game 5 hero who drained seven 3-pointers despite playing with a back that will require surgery.

Miller may retire, or the Heat may use the amnesty clause on his contract to create cap space. But Miami will enter next season with essentially the same team that won the title, a flawed squad with the game’s best player (James), a superstar perhaps in decline (Wade), and a solid third option (Bosh).

The Heat will be a difficult, but not impossible, team to overcome. You can assume that James will return motivated to prove his first title wasn’t a fluke, but can the same be expected from Wade, and will Mario Chalmers be able to produce for a second consecutive year?