It was a long night for Kevin Durant and Russell Westbrook, who combined to go 15-for-55 in Oklahoma City’s loss to Dallas. (AP Photo/Alonzo Adams)

It’s easy to find reasons to excuse the Oklahoma City Thunder’s 85-84 loss to the Dallas Mavericks in Game 2 of their first round playoff series Monday night.

It’s unlikely Kevin Durant is going to ever shoot as badly as he did in Game 2 – going 7 for 33 overall and 2 for 10 from three-point range – in a playoff game, let alone in this series. If the ball leaves the hand of Thunder center Steven Adams a tenth of a second sooner on a tip-in at the buzzer, Oklahoma City wins the game and takes a commanding 2-0 lead in the series. Raymond Felton isn’t likely to go for 21 points and 11 rebounds again in a game this series.

But here’s the truth about this game: the Thunder just lost a home playoff game to a team that was without Chandler Parsons, J.J. Barea and David Lee before tip, lost Deron Williams during the game and was playing Felton at point guard and Salah Mejri at center in the closing minutes. There simply are no excuses that should lead to a team with Oklahoma City’s talent losing that game at home.

Yet that’s exactly what everyone has come to expect from this Thunder team over the past few months. Despite having two of the best players in the NBA in Kevin Durant and Russell Westbrook, Oklahoma City has been the second-worst fourth quarter team in the NBA since the all-star break – second only to the woeful Phoenix Suns – and entered the playoffs a dreadful 3-12 in 15 games decided by five points or less since the all-star break, as NBA.com’s John Schuhmann pointed out at the start of the fourth quarter Monday night.

Once again, the Thunder came up small in a game’s dying moments. Despite Dallas trotting out a lineup featuring a clearly tired Dirk Nowitzki, rookie Justin Anderson, Felton and Mejri, the Mavericks still managed to outscore the Thunder 16-8 in the final six-plus minutes of the game. Oklahoma City missed shot after shot, going 3 for 16 overall and 1 for 6 from three-point range, with Westbrook and Durant combining to go 2 for 13.

For a team that fired Scott Brooks last summer, in large part, to freshen up an offense that many considered too simplified and stagnant to win in May and June, the Thunder looked like the same team as the past several seasons. While Coach Billy Donovan drew up several nice out-of-bounds plays late in the game – getting Westbrook a wide-open look and Durant two others inside the final couple of minutes – none went down, giving Dallas the chance to steal the game.

Then there’s the matter of some of Donovan’s coaching decisions in the game’s final minutes. In addition to the stagnant offense, he also had Dion Waiters on the court for most of the final six minutes, despite the fact Waiters contributed nothing besides a missed corner three-pointer. It’s hard to believe, especially given who Dallas had on the court, that it wouldn’t have made more sense for the Thunder to have Anthony Morrow – one of the best shooters in the league – in that spot to better space the floor.

Meanwhile, when someone is as off as Durant was Monday, perhaps it’s time to stop shooting? Imagine the reaction if Westbrook had gone 7 for 33 in a Thunder loss? It would’ve been a lot uglier than what is happening now. Part of the reason Oklahoma City has been so bad in the fourth quarters of these games is its offense bogs down, and the game turns into Westbrook and Durant trying to beat the opposition by themselves rather than trusting their teammates.

Now, something should be said about the Mavericks, and specifically Coach Rick Carlisle. It’s truly remarkable what he’s been able to coax out of this Dallas roster, given all the injuries. That he’s getting big playoff performances from guys like Felton – whose career was left for dead after bouncing around from multiple teams in recent seasons – and Mejri – who played in all of 34 games this season – only speaks to the job he’s done there.

But, with that said, where does all of this leave Oklahoma City? The Thunder are still almost certain to win this series, and will likely do so by sweeping the next three games. But the issues that have cropped up repeatedly for this team all season long – namely its inability to close out games, and its always porous defense – aren’t going away.

Looming on the horizon, assuming the Thunder take care of business against Dallas, is yet another showdown with the San Antonio Spurs in Round 2. And rest assured that if there is any team that’s going to keep on executing in the fourth quarters of games, it’s San Antonio.

Just look at the last time these two teams played a game that mattered, on March 12 in San Antonio. Like they did so many times this season, Oklahoma City went into the fourth with a two-point lead. And, as the fourth wore on, the Spurs slowly pulled ahead and pulled away, winning by eight.

Everyone has been waiting for Oklahoma City to flip the switch, to start trying on defense, to start looking like a team capable of going toe-to-toe with the Spurs and Warriors and emerging from the Western Conference.

Maybe that day will come. There’s still time for it to happen. But, after 84 games this season, there’s little reason to expect it will.