Thunder win latest chapter of rising NBA rivalry

What is a rivalry? Can it be sold based on potential and advertised by the names on the back of the jerseys? Must true rivalries be built in the playoffs, created once both sides have tasted the bitterness of defeat on the game's biggest stage? Can it spawn in an instant? Is there a telltale sign? "We should've won the game,'' said Dallas Mavericks coach Rick Carlisle after his team's 95-91 loss at Oklahoma City on Monday, adding that his team was "deserving of a better outcome." "We gutted this one out, man," said Kevin Durant from the winning locker room, where the Thunder celebrated their 13th straight home win. And maybe that's the spawning. The regional ties, the Western Conference Finals battle last season, the peaking of the champion Mavs and the climb of the possible-heir Thunder, a contempt-breeding sixth meeting already this season (counting a preseason doubleheader) and the capper: A thrilling game in which both combatants think they deserved to win. When Dirk Nowitzki erased a late deficit by hitting four consecutive 3-pointers on his way to a game-high 27, Thunder fans had to have sighed, "Not again." When OKC's James Harden responded with 14 fourth-quarter points to seal the victory for the Western Conference leaders, a not-'til-the-end victory that included some uncharacteristic execution gaffes on Dallas' part, everyone involved felt a surge of passion. As befits a budding rivalry. This one isn't ready for NBA annals or anything like that. But the Oklahoma City Thunder vs. the Dallas Mavericks is on its way. Cast at vastly different stages of their team arc, one fighting to carve their name in the stone halls of league history, the other having tasted the air at the top of the mountain after having become entrenched among the NBA's elite after winning at least 50 games for 11 straight seasons. The Mavericks bid their way into staying on top for this night with a combination of Dirk and defense. Dallas' Shawn Marion continued his defensive brilliance, though the Mavs often relied on a zone in an attempt to limit the penetrating abilities of Kevin Durant and Russell Westbrook. To an extent, this approach was effective. As a pair, Durant and Westbrook hit only 12 of their 38 shot attempts (31.8 percent). Oklahoma City shot 38 percent, just the fourth time all season they've bee n held under 40 percent. And the 95 points is seven shy of their average. If not for the dominance of Harden in the final period, where he was 3-of-3 from the floor and 7-of-7 from the line and perhaps a call here or there the outcome of this game is likely altered. Westbrook and Durant did not condemn Dallas to a loss. That's a positive for the Mavs. But this is a rivalry, and a fairly even one. So in Oklahoma City, the Thunder can congratulate themselves on having won without ideal games from their two standouts. In direct contrast to Oklahoma City sixth-man Harden's performance in the games most impactful moments was that of Dallas sixth-man Jason Terry, who pounded the ball into the court seemingly unaware of the time on the clock in several key moments. At the end of the third quarter, he essentially dribbled the clock out for the Thunder, leaving the Mavs without a chance to take the final shot despite the fact that they took possession with 10 seconds left in the quarter. In the game's final 46.3 seconds, he repeated this mistake twice more, though with slightly different resultsmeaning, there was at least a shot attempt, a poor one. On the second-to-last possession, Terry was too casual in getting the play underway, and after a Thunder defender tipped a pass, was again slow to attack, leaving him the sole option of a contested-fadeaway jumper. When Dallas had one more chance, still in a one-possession game after Durant split a pair of free throws with 13.9 seconds remaining, Terry failed to get the Mavericks best player, Nowitzki, a touch. Instead he found himself driving into traffic and to the baseline, found himself missing a wide-open Kidd in the paint, found himself failing to find the hot hand in a momentarily-open Dirk, before delivering an extremely late and poorly-spaced shuffle to Kidd, who was leaning out of bounds, leaving Kidd no choice but to immediately volleyball it back to Terry, who again took a contested jumper and again missed. "We haven't really been sharp on our execution at the end of ballgames and that's hurt us," said Terry, who scored nine of his 18 points in the fourth quarter. "Not a big concern because I know the type of team we are. We thrive in those situations. We've got to just keep clawing it out. Eventually it will swing our way and we'll pull these games out, but it's been a thorn in our side the entire season." Added up, Dallas scored zero points in the last 2:46 of this game and were outscored 8-0 down the stretch. The veteran team that prides itself on being great late? This year's Mavericks are now 6-8 in games decided by five or fewer. The roles of last season's playoffs were reversed. The wily veteran Mavericks failed to execute in the game's closing moments, while the Thunder did what they had to in order to win. Oklahoma City has finished the season series, winning three of four, with two of those victories coming in the final seconds. Perhaps another step has been taken in the construction of a true rivalry. The regional aspect is in play and the quality of teams is just right and the anger is aroused. The rivalry is coming.