SACRAMENTO, Calif. — A widespread assumption is that the Oklahoma City Thunder acquired center Kendrick Perkins at the trade deadline with the sole purpose of preparing to do battle with the Los Angeles Lakers in the playoffs. And that just isn’t true. Perkins’ acquisition was a part of the Thunder’s long-term plan to build a true championship contender. But to be the best, you of course must beat the best. With Perkins in the mix, the Thunder was able to do that, at least for one game in the regular season. The Thunder downed the Lakers, 120-106, on Sunday night, marking the first time in the franchise’s Oklahoma City era that it has beaten the Lakers in L.A. Perkins played a big part. First, he talked the talk, calling out Lakers coach Phil Jackson as “arrogant” and labeling forward Pau Gasol “soft.” Then he walked the walk, helping to limit Lakers center Andrew Bynum to 12 points and hold Gasol to four rebounds. Perhaps most importantly, Perkins stood up to the back-to-back defending champs. He locked horns with Kobe Bryant, all but putting the Lakers star in a headlock and then daring any Laker to do something about it. And he flustered Bynum so much that the Lakers’ big man threw the ball in Perkins’ chest. Perkins didn’t budge. For his skirmish with Bryant, Perkins picked up his seventh technical foul since debuting with the Thunder on March 14. “That’s a good number,” said Thabo Sefolosha. Said Serge Ibaka: “That’s playoff mentality.” Perkins explained his comments about Jackson and Gasol after the win over the Lakers. “That was my opinion from the past battles that we’ve had in the past playoffs,” Perkins said. “It wasn’t nothing that I said out of character or was too crazy. I just spoke my mind in a way. The thing is you’ve just got to back it up.” Perkins has done plenty of that, too.