SACRAMENTO, Calif. -- CJ McCollum and Damian Lillard get much of the credit for the Portland Trail Blazers' unlikely rise in the Western Conference standings, what with their backcourt ability to shoot and dart to the hoop.

But the Blazers bring a lesser known weapon to the floor each night, too, and it made the difference in a 115-107 victory over the Sacramento Kings at Sleep Train Arena on Tuesday that moved Portland another step closer to a playoff berth.

"For the season, we've been a good offensive rebounding team," Portland coach Terry Stotts said. "It's been a strength of ours."

The Blazers (42-37) dominated the Kings 19-3 on the offensive glass and grabbed three in a row during one sequence late in the fourth quarter, the last of which led to McCollum's 3-pointer that capped his 30-point night and finally put Sacramento away.

Lillard added 22 points, and McCollum knocked down five 3-pointers during his 11-for-20 night for Portland. His 3-pointer, after Mason Plumlee grabbed two offensive rebounds following McCollum's own offensive board, capped a 7-0 run that put Portland ahead 106-96 with 2:55 left.

Forward Maurice Harkless added 20 and a career-high 16 rebounds as Portland beat the Kings (31-47) for the sixth straight time. Harkless had seven offensive rebounds and center Mason Plumlee grabbed six.

"You've gotta give a lot of credit to Mason and Mo," Stotts said. "Offensive rebounding is a talent. You really don't coach it."

The Trail Blazers (42-37) stayed a half-game behind the Memphis Grizzlies (42-36) in the race for the fifth spot in the West and moved three games ahead of the ninth-place Houston Rockets (38-39). Portland can clinch a playoff spot with two more victories, two more Rockets losses or one win and one Houston loss.

"It's huge," Harkless said of the rebounding advantage. "It energized your team when your shots aren't falling. It's an easy way to get points."

The Kings (31-47) will be missing the playoff fun for the 10th consecutive season, but they did have some individuals add to their record seasons.

Guard Rajon Rondo put his name on another line in the Sacramento record book, recording his sixth triple-double of the season with 27 points, 12 assists and 10 rebounds. Rondo surpassed Chris Webber's 1999-2000 triple-double total.

Rondo also moved past Norm Van Lier for seventh place on the Kings' all-time assist list. He has tallied at least 10 assists in 51 contests, a Sacramento record, and the most for the franchise since Nate Archibald set the team mark with 56 for the Kansas City-Omaha Kings during the 1972-73 season.

DeMarcus Cousins led Sacramento with 30 points and added nine rebounds, etching his name into the record book, as well. Cousins' 26th contest with at least 30 points tied Mitch Richmond's Sacramento record set during the 1996-97 campaign.

"No," Cousins said when asked if the record was something he'd view as a positive in a season mostly composed of negatives for the Kings. "I guess you could look at it that way when you look at season, but no."

Cousins also picked up his league-leading 17th technical foul when he shoved Trail Blazers guard Gerald Henderson while on his way to the bench during a timeout. Cousins, who already is scheduled to sit out Sacramento's final two games for rest, would miss one of the two in which he is scheduled to play with a suspension if he picks up another one.

The Kings led for much of the night despite the disadvantage on the offensive glass. But they made just 17 of their 40 shots in the second half.

"We were much better defensively in the second half," Stotts said. "We rebounded the ball well, and it allowed us to get a little more rhythm to our offensive game."

Seth Curry scored 17 points and pulled down six rebounds for Sacramento.

NOTES: Sacramento played without F Rudy Gay, G Darren Collison, and C Kosta Koufos, all of whom were given the night off to rest. ... Blazers G Damian Lillard needs seven 3-pointers in Portland's final three games to tie G Wesley Matthews' franchise record of 826. He already became the first player since Clippers G Chris Paul to record more than 450 assists in each of his first four season. ... Kings F Omri Casspi (strained right hamstring) missed his second consecutive game. Casspi is expected to return in time to play in Sacramento's final four contests. ... The Blazers played their final road game, already assured of their worst campaign away from Portland since 2012-13. They face Oklahoma City, Minnesota and Denver in their final three games at home, where they already secured their ninth straight winning season.