Chehalis' Delanie Otten scored 25 points for the Tigers.
"Otten had a great night," Tumwater coach Nick Greenwell said. "Masey Schrader really stepped up big for us in the third quarter. She had a couple nice layups that changed the pace of the game."
Despite Tumwater's struggling offense, the Thunderbirds were able to hold on to the lead.
"We're shooting 48 percent on the year; tonight we shot 35 percent," Greenwell said. "It was a hard-fought game and we came out a little bit ahead at the end."
Ashley Andrews scored 11 for the T-Birds. Morgan Schwegler scored nine.
Black Hills 59, Elma 38
The Wolves got an all-around effort as all 10 players scored to distance themselves from struggling 2A Evergreen foe Elma.
Freshman post Chelsea Haskey gathered attention with a game-high 14 points and nine rebounds off the bench for the Wolves. Chelsey Kaasa added eight points, five steals and three assists.
Katie Colard's 11-point effort led Elma (4-7 league, 8-7 overall).
Black Hills (8-3 league, 14-4 overall) faces Centralia at 7:30 p.m. Thursday.
Clover Park 50, Yelm 29
The Tornados dissipated in the second half to give 3A Western Conference foe Clover Park (3-6 league, 8-8 overall) a commanding victory after a competitive 14-14 tie at halftime.
Yelm shot 12-of-34 from the field and was led in scoring by Kayla Helland's eight points.
Yelm (5-4 league, 10-7 overall) hosts an undefeated Lakes squad Friday at 7 p.m.
Lakes 45, North Thurston 34
It wasn't the quality performance one could expect from an undefeated Lakes squad but it worked as the slumbering 3A Western Cascade teams struggled to score.
"Both teams were terrible," Lakes assistant coach Rob Morrison said of the low-scoring offenses. "Good defense on both sides. Pretty tenacious."
The Rams (4-6 league, 8-9 overall) could also attest to breaking their defensive woes of late but couldn't generate any shooting rhythm.
"We were missing way too many layins," Rams coach Alana Erickson said. "Defense has been our problem, but we stepped up on the defensive end. We executed the game plan real well. We wanted to make them shoot from the outside, but we got killed on the offensive rebounds."
Micha Pringle scored nearly half of North Thurston's points with 15.
Lakes improved to 9-0 in the league and 12-3 overall.
Mary M. Knight 54, Washington Deaf 30
Mary M. Knight jumped out to a 25-6 first-quarter lead and cruised to a home victory in the Class 1B district playoff opener.
Shelby Adsero scored all nine of her points in the opening quarter, and she finished with a team-leading 11 rebounds for the Owls (13-6).
"Our defensive pressure forced a lot of turnovers, and we got started off hot," Owls coach Lance Valley said. "We controlled the boards pretty well at both ends of the court.
"Plus, we were pumped up for our first district game."
Teryssa Toppano scored 14 points and grabbed six rebounds for Mary M. Knight. Shareese Willey added six points and five steals, and Amanda Vera came off the bench to contribute three points, four steals and four assists.
NORTHWEST CHRISTIAN 47, NASELLE 37
Standout Lindsey Wagner scored 2 points but still hauled down 11 rebounds despite reinjuring a sprained ankle. And the Navigators overcame an 18-17 halftime deficit to pull away from the Comets.
Kathleen Post came up big on offense with 21 points and added a solid defensive effort in the place of Wagner. Teammate Elianna Isoz had her best scoring game of the season with 14 points.
Rainier 38, Rainier Christian 29
Although the Mountaineers were barely removed from playoff contention, they still had a chance to break even for their season closer.
Kaylene Livingood hit four 3-pointers in the first half and scored 15 points overall to help the Mounties reach the .500 plateau at 10-10 overall.
Rainier, under first-year coach Dave Wasankari improved from a 2-18 record and narrowly lost a district bid after losing two games to Montesano, the 1A Evergreen team with the same league record.
"We competed," Wasankari summarized.
RIVER RIDGE 57, HOQUIAM 30
Courtney Bluhm paced a balanced attack with 16 points as the Hawks expanded a 12-11 lead to 48-20 during the middle two quarters.
Sophie Russell scored 12 points, and Santia Sanders added 10, as River Ridge improved to 16-0 for the season and 11-0 in the Evergreen Conference.
Shelton 58, Timberline 34
The Highclimbers quickly put the game out of reach with a 32-11 halftime lead to dominate their 3A Western Cascade conference game.
Annie Johnson led Shelton (4-6 league, 8-9 overall) with a game-high 17 points and Timberline got their most productivity from Katie Everson's 14 points. Those were the only two players in double digits.
Timberline (0-10 league, 2-15 overall) hosts Aberdeen Saturday at 5 p.m.
Winlock 52, Tenino 29
The Beavers couldn't burrow out of the defensive dam Winlock built in a Southwest 1A Evergreen Division game wherein they shot 11-for-38.
Adelle Love and Maggie Nelson were Tenino's main scoring weapons in attempts to counter a Winlock squad that shot 21-for-48.
Tenino (0-11 league, 1-18 overall) has a chance for revenge hosting Winlock next Thursday at 7:30 p.m.
Clover Park 66, Yelm 56
Clover Park sophomore point guard Adam Bowen scored 17 points in the fourth quarter to help the Warriors beat the Yelm Tornados.
Bowen finished the night with 24 points.
After three quarters of play at Clover Park, the score was tied at 36. But Bowen's performance was enough to tip the tide in the Warriors' favor.
Matt Geverola and Derrick Davis were the only other Clover Park players scoring in double figures. Each had 11.
Kevin Houlihan scored 25 for Yelm.
Lakes 79, North Thurston 57
North Thurston stumbled at home against Lakes, losing 79-57.
Lakes center Kavario Middleton led the Lancers with 21 points. Four Lakes players scored in double figures.
"Middleton hurt us," Rams coach Tim Brown said. "Lakes just outplayed us."
The Rams were led by Josh Brewer and Will Sharp, who scored 18 points each. Brown said the Rams had a good game from both Brewer and Sharp.
RIVER RIDGE 75, HOQUIAM 58
The Hawks opened both halves in a hurry en route to grabbing a key Evergreen Conference victory over the Grizzlies.
Donald Terry led the way with 21 points, Anthony Thomas scored 14 and Maurice Bouchet added 11 as River Ridge took a 24-9 lead after the first quarter. The Hawks then watched Hoquiam pull within 39-29 at the half, then built the margin back 64-41 after three quarters.
"We came out with a lot of energy rebounding, and we took good shots," River Ridge coach Jeremy Landram said. "Plus Dontavius Fleming and Rodney Smith did a 'heckuva' job on their Joey Wayman and held him to eight points.
"That gives us three wins in our last four games and makes our game at Tumwater on Friday a very big game for us."
The Hawks broke a three-way tie with Hoquiam and Aberdeen for the final postseason slot and moved within a game of fourth-place Black Hills.
The top four teams get direct berths to district, while the fifth team has to play a pigtail game against a team from the south for a spot.
Shelton 53, Timberline 38
Curtis Trondsen scored 20 points to lead Shelton, which led 20-7 after one quarter and 32-16 at halftime.
"We had a very good first half," Shelton coach Mark Jensen said. "We shot the ball pretty well early, and once we got the lead, it was tough for them to come back.
"We did a good job taking care of the basketball, which is something we've had trouble with at times."
Shelton improved to 12-7 overall and 6-4 in the Class 3A Western Cascade Conference.
Devlin Payton scored 12 points to lead Timberline (3-14, 2-8).
Tenino 66, Forks 46
The Beavers dulled Forks' offensive effort early to establish a 10-3 lead after the first quarter and punctuated the final quarter with an overpowering 24-9 performance.
Marc Hedden led Tenino with 22 points as the Beavers got more than a third of their points from the foul line going 25-of-37.
Tenino travels to Winlock at 7:30 p.m. Friday.
Winlock 62, Rainier 59
Rainier, down 15 points at halftime, was able to come back and lead by one with 1 minute, 10 seconds to go in the game.
But it wasn't meant to be for the Mountaineers.
Winlock spoiled senior night at Rainier, winning by three points.
"It was a tale of two halves," Rainier coach Josh Frunz said. "We just couldn't quite get the job done in the end."
Lone senior Scott Eygabroad led the Mountaineers with 19 points. Kyle North added 14.
"Everybody contributed with steals," Frunz said. "Matt Wilson had a couple good steals in the fourth quarter. Jacob Fox had some key buckets in the fourth. Eygabroad really worked his heart out.
"I really respect the kids for the way they handled themselves in the game."