Starting the playoffs against defending NBA champion Dallas provided the Oklahoma City Thunder a chance to show how far they've come after losing to Mavericks last year.

It didn't take long for the Thunder to finish off that challenge.

Oklahoma City handed the Mavs the first four-game sweep in franchise history, blowing through two games in Dallas to return the favor for last year's postseason heartache - winning one in a blowout and one with a fourth-quarter comeback.

"It was a tough, tough series for us last year. Obviously we didn't get the outcome we wanted,'' All-Star point guard Russell Westbrook said. "It taught us a lesson.

"We needed to come back this year with a lot more toughness, and I think we did that this series, and this season, and hopefully we'll continue to do that.''

First, the Thunder took a hard-earned day off Sunday while waiting to find out whom they'll face in the Western Conference semifinals. Kevin Durant and Co. won't know until at least Tuesday night, and possibly not until Saturday, whether it will be the Los Angeles Lakers or the Denver Nuggets.

The Lakers took a 3-1 series lead by winning 92-88 in Denver on Sunday night.

The Thunder won the season series against both potential opponents 2-1, losing to both in the final week of the regular season with top reserve James Harden out for the last part of the Lakers game and all of the Nuggets game after getting elbowed by L.A.'s Metta World Peace.

The sweep could give Oklahoma City its longest break of this lockout-shortened season. The only time the Thunder had more than three straight days off was a five-game layoff over the All-Star break.

The rest will be welcomed by center Kendrick Perkins, who left the clinching Game 4 victory Saturday night with a strained right hip.

"Perk is a big part of what we do,'' Durant said. "Just his leadership and toughness out on the floor was definitely missed in the second half, but his health is way more important to us. More than anything, we just wanted to get the win for him.

"Hopefully these next few days he gets some rest and can be ready for the next series.''

Perkins was considered day to day. He missed only one game all season after missing most of last season recovering after he had knee surgery and then re-injured the knee after his comeback.

"It's tough to see our big fellow go out, a guy that gives his all every single minute he's on the floor, gives his body for us,'' Durant said. "Hopefully, he's all right.''

Already, the Thunder have cleared one enormous hurdle, the one that tripped them up in a 4-1 defeat in last year's Western Conference finals. The Mavericks changed since then, sticking with the same core but replacing center Tyson Chandler - this year's NBA Defensive Player of the Year - along with J.J. Barea, DeShawn Stevenson, Caron Butler and Peja Stojakovic.

Still, Oklahoma City was able to avoid the late-game struggles that allowed Dirk Nowitzki to guide Dallas to the series win last year.

"Since day one, since I got here, it's just all about building and growing and getting better every single day, and I think that's what we've done,'' Durant said.

"We're not satisfied. You've just got to keep pushing.''