Johansen scored the tiebreaking goal with 1:37 remaining after a turnover by Joe Pavelski and the Blue Jackets overcame a blown two-goal lead in the third period to beat the San Jose Sharks 4-3 on Sunday night.
"It feels like a little bit of destiny with this team," said forward R.J. Umberger, who assisted on the winning goal. "We're just a very confident team. We feel like we are underdogs every night. We're proving people wrong. This team believes a lot and it just feels like our destiny that we're to make the playoffs. We want to make it more than anything.
Mark Letestu scored twice and Vinny Prospal also scored for the Blue Jackets, who moved into a tie for seventh place with Minnesota in the Western Conference with 51 points—three points ahead of Detroit and Dallas for the final playoff spot. Columbus has played one more game than the Wild and Stars, and two more than the Red Wings.
Sergei Bobrovsky made 32 saves for the Blue Jackets, who won for the sixth time in seven games as they try for the second playoff berth in franchise history.
The game came down to that late turnover by Pavelski, who lost the puck trying to come out of his own zone, setting up Johansen's second game-winner of the season.
"I was licking my chops," Johansen said. "That was for sure.
It was a wild swing of emotions in the third period, especially for Pavelski. The Sharks rallied from 3-1 down to tie the game on his power-play goal with 5:03 remaining only to miss a chance to clinch the playoffs when they lost in regulation at home for just the second time this season.
"It was right there for us obviously," Pavelski said. "It's tough. You never want to make a play like that at the end. You understand where you are in the game and you understand these things do happen once in a while. It's tough when they do, but we have to move on and get better from this and I have to try to execute better next time."
Marty Havlat and Andrew Desjardins also scored and Niemi made 18 saves in his 23rd straight start for the Sharks, who need one point to clinch their ninth straight playoff berth.
While San Jose still has three more games to clinch the playoffs, this loss dealt a blow to the team's hopes to get home-ice advantage in the first round. The Sharks fell two points behind fourth-place Los Angeles in the standings, but remained one point ahead of sixth-place St Louis. San Jose would lose the tiebreaker to both teams based on fewer regulation and overtime wins.
"I wasn't concerned with getting a point and putting an X by our name," coach Todd McLellan said. "I was concerned about our game. It's our game that will get us there or won't get us there. Forget about the clinch part."
McLellan was upset about his team's sloppy, lackluster play for much of the night. San Jose had 17 giveaways in the game with a bad pass by Brad Stuart setting up Prospal's goal that made it 2-0 and Pavelski's turnover leading to Johansen's game-winner.
"Our forecheck is a strength of ours," Blue Jackets coach Todd Richards said. "If we are forechecking hard and we're after pucks and using our speed and our size that's playing to our strengths. Turnovers in this game whether it was them or us. Turnovers are huge."
The Blue Jackets swept the three-game season series from San Jose, winning for just the third time in 22 games at the Shark Tank.
After falling behind 2-0 when Prospal scored on a breakaway following Stuart's turnover, the Sharks got back into the game when Logan Couture fed Havlat in front for a tip-in midway through the second period.
But San Jose then allowed a rare power-play goal at home to fall back behind by two. With Matt Irwin in the box for interference, Letestu beat Niemi with a blast from the left point for his 12th goal of the season and first multigoal game since March 8, 2012, against Los Angeles.
Columbus had been 0-for-17 on the power play over the last eight games.
NOTES: San Jose had been 16-1-5 at home, with the only regulation loss coming to Chicago on Feb. 5. ... The Sharks have allowed seven power-play goals at home this season. ... Columbus C Artem Anisimov (concussion), F Matt Calvert (broken finger) and D Nikita Nikitin (lower body) sat out with injuries. ... San Jose D Jason Demers, who was hurt in the third period on Thursday, missed the game and was replaced by Scott Hannan.