Tumwater (11-5, 7-3) trailed 36-31 midway through the fourth, but the T-Birds dug deep to remain in third place.
"We just had to find a way, and we did," Tumwater coach Marty Reid said.
Johnson gave the T-Birds a 39-38 lead with a key layup, then added another one and picked up a foul for a three-point advantage.
Johnson missed the free throw, but Hank Bryant grabbed the offensive rebound and tossed it back to Johnson for a key six-point swing with less than two minutes to play.
Nick Smith, who tallied a team-high 14 points along with five assists and five steals, combined with Jeff Ostlund to shoot 4-for-4 from the line to seal it down the stretch.
"The kids did a great job. They didn't give up," Reid said. "This was definitely a character win for this group. I don't think we played our best game, but it was a very important game for us to win.
"This time of the year, you're going to have to grind some out if you're going to keep playing."
CENTRALIA 52, CHEHALIS 34
Isaac Moog scored 19 points and grabbed nine rebounds as the Tigers avenged their only 2A Evergreen Conference loss of the season and pulled into a first-place tie with the Bearcats.
Centralia (13-4, 8-2) led 27-11 at halftime and limited Chehalis to 3-for-11 shooting in the opening quarter. The Tigers pulled away in the final minutes, sinking seven of eight attempts at the line in the fourth quarter.
Sean Meehan pulled down 12 rebounds for the Tigers and Brandon Abbott led the Bearcats (13-3, 8-2) with 14 points.
RIVER RIDGE 79, ELMA 62
Donald Terry scored 25 points and the Hawks exploded for 27 first-quarter points to beat the Eagles.
River Ridge set the tone early when Anthony Thomas converted an alley-oop pass for a dunk for the first points of the game.
"They came out in a zone and our guys, Maurice (Bouchet) and Donald (Terry) shot the ball really well," Hawks coach Jeremy Landram said. "Our press caused them some problems and we moved the ball really well in our fast breaks. We got lots of easy layins off our ball movement."
Bouchet finished with seven points while Thomas and Dontavius Fleming had 10 apiece.
Mary M. Knight 73, Wishkah Valley 38
Lucas Christianson scored 16 points, Sean Brehmeyer had 15 and Jeremy Prouty added 11, leading the Owls to a season sweep of Wishkah Valley.
Mary M. Knight finished the regular season at 12-6 overall and 10-5 in league and begins league playoffs Wednesday at Montesano.
"We've had a great season," Owls coach Tim Diggle said. "Tonight, we were getting the open shot and making it. The defense was ready to play, too."
Mary M. Knight led 14-5 after the first quarter and 36-17 at halftime.
Christianson, one of four seniors on the team, played point guard rather than his regular position of shooting guard.
"Everybody rotated a little bit," Diggle said. "We're staying like we are. It's working good."
Lakes 80, Shelton 62
After an even first quarter, the Lancers broke the game open with a 22-11 run in the second and never looked back as Lakes outdistanced the Highclimbers.
Shelton just couldn't find an answer for the Lancers' Kavario Middleton, who scored 27. Too big to be defended by a guard, and too quick to be stopped by a post, Middleton turned out to be too much for the Highclimbers to handle.
"They shot the ball awfully well and we didn't defend them as well as we hoped to," Shelton coach Mark Jensen said. "And Middleton is a pretty solid player, to put it mildly."
The Lancers went 32-of-50 from the floor in the win. Shelton (11-6 overall, 5-3 WCC) hit at a respectable clip, 22-of-44, but couldn't match Lakes down the stretch.
"We turned the ball over too much," Jensen said. "They're very athletic and very quick and caused some problems for us with turnovers."
Clover Park 55, Yelm 54
The Tornados ran out of wind in the fourth quarter for a third consecutive blown lead to lose to fellow league cellar-dweller Clover Park (2-6 league) in the 3A Western Cascade Conference.
Despite tremendous scoring from guard Kevin Houlihan, his 23 points could not overcome a fourth quarter in which Yelm
(1-5 league, 5-8 overall) scored five points total.
"It's just making the plays down the stretch," Yelm coach Luke Salme said. "The other teams turn up the pressure and we're not responding like we need to. It's like we're trying to avoid losing instead of trying to win and that's not working."
The Tornados had the chance for a game-winning possession but missed two shots.
Hoquiam 44, Black Hills 41
The Wolves slipped into a scoring trap in the third quarter and couldn't recover on the road against a Hoquiam squad with a similar division record.
Kyle Fugere was Black Hills' leading scorer with 13 points, and the Wolves outscored Hoquiam every other quarter except the third, when they were outscored 11-5.
"The groups of guys we put on the court had great effort," Wolves coach Tal Wold said. "I was proud, everyone on the team kept fighting and gave us a chance."
The Wolves went up by one with 30 seconds remaining but Joey Wayman came up with a clutch 3-pointer to put the Grizzlies ahead for good.
"They have a great atmosphere there," Wold said. "Hoquiam's a neat place. Almost like a college facility."
Olympia 51, North Kitsap 46
The Bears have nudged their way into a berth in the 4A Narrows Bay playoffs after winning a road game over North Kitsap (2-12).
Led by Casey Stevick's 15 points, the Bears (6-8 league, 9-10 overall) played without Clay Longmire but got notable scoring efforts from Conrad Davis-Febert and Taylor Hower.
"A great win for us playing without Clay," Olympia coach John Grosey said. "It gives us a chance to keep playing another week."
Longmire won't be back for Olympia's game against South Kitsap, but Grosey is hoping for a playoff return next week.
ONALASKA 41, TENINO 30
Maggie Nelson scored 10 points and Cassondra Smith and Stephanie Korpusik each grabbed nine rebounds, but the Beavers struggled through a poor shooting night in an attempt to pick up their first Southwest 1A Evergreen Division win.
Tenino (1-14, 0-8) shot just 12-for-46 from the floor, but coach Bill Buthorn said he was encouraged by his team's play in the second half.
"We've only got a handful of kids right now and some of them played almost the whole game, but they did a good job," Buthorn said. "It's been a long season, but the kids are still working hard."
Freshman Adelle Love scored nine points for Tenino, which outscored Onalaska 20-17 in the final two quarters.
Olympia 52, North Kitsap 44
The Bears clinched a 4A Narrows Bay entry as the fourth seeded team with a home win over North Kitsap.
Natalie Kirk scored 12 points and pulled down 12 rebounds to keep the Vikings from striking distance.
"Kirk had a monster game," Bears coach Pete Mortlock said. "Defensivley, we brought a lot of energy. Our kids did a nice job."
Olympia continued to trudge on without freshman Marnie Brown who is trying to heal a foot injury for the team's new playoff potential.
"Marnie's a big part," Mortlock said. "Big encourager. Mature beyond her years. She brings a positive presence to the bench and she's the girl who had 12 points against (North Kitsap) last time."
Mary M. Knight 48, Wishkah Valley 33
Coach Lance Valley is getting productive use from so many Owls that it's tough to see a scoring favorite emerge any given night.
"Basically, all 10 players I feel comfortable playing," Valley said. All 10 players combined to hold down visiting Wishkah Valley from coming back in the Pacific 1B league game.
Shareese Willey helped the Owls off to a big start from the scoring perch with seven of her 10 points in the first quarter.
Alicea Scott had five points and 13 rebounds with Shelby Adsero and Teryssa Toppano scoring nine points with 11 rebounds apiece to contribute.
North Thurston 134, Clover Park 29
Winning every race but one, North Thurston easily outdistanced Clover Park. In five of the nine individual events, the Rams swept the Warriors.
North Thurston was able to add to its stable of district-qualified swimmers, with Loc Hua qualifying in the 100 breast (1:12.63) and Scott Groenwald in the 100 back (1:09.93). The Rams will send at least nine swimmers to the Class 3A District IV meet next weekend at Hazen High School in Renton to compete against 25 other teams.
"We've got nine guys at districts and all three relays," North Thurston coach Josh Stottlemyer said. "And actually, a couple more that will get in as wild cards - there are quite a few guys that are really close."