Jokiharju made it 4-2 at 5:51 with a wrist shot from the high slot to the glove side for his first goal with the Bruins.
Arvidsson scored an empty-net goal at 16:23 for a 5-2 lead.
Johnston brought the Stars to within 5-3 while on the power play at 19:02, lifting a backhand shot over Korpisalo's blocker from in front.
“Not enough,” Johnston said. “We’re playing a lot of hungry teams who are fighting for their lives. You can’t expect to be perfect and dominate a full 60 every day, but when we play our way more often than we don’t we’re really successful, so it’s just a matter of doing that.”
Arvidsson scored a second empty-net goal at 19:47 to complete the hat trick and secure the 6-3 final.
“We have fun together and we put a lot of emphasis on being hard on each other, and really pushing each other,” Arvidsson said. “In that regard, we’re really happy where we are, but we have a job to finish to get ready for the playoffs.”
The Bruins have seven games remaining, including five on the road where they are 15-14-7. Arvidsson admitted the team is playing with a lot of confidence, but needs to be better on the road.
“We’re going on a road trip and we’ve got to get the job done now,” he said. “We’ve got to start off good and just build and improve our game on the road."
For Dallas, five of its remaining seven games are on home ice.
“We obviously want to come back home and get ourselves back to where we need to be,” Duchene said. “We’ve got another level we can get back to. It’s normal after a streak to sag a little bit. We were neck-and-neck with Colorado and they pulled away from us a little bit. We’ve got seven left now and it’s time to ramp it up and ascending with our game going into the playoffs.”
NOTES: Pastrnak set a new career high for assists in a single season with 66, besting his previous high of 63 he had in 2023-24 and 2024-25. ... Arvidsson has nine points (five goals, four assists) in a four-game streak. ... With an assist, Boston forward Pavel Zacha set a new career high for points in a season with 60 (28 goals, 32 assists), besting his previous high of 59 which he set during the 2023-24 season. ... Pastrnak recorded his 106th multiassist game, tying David Krejci for sixth in franchise history. ... Oettinger played his 300th NHL game. ... Stars forward Michael Bunting did not play after leaving a 2-1 overtime loss at the Philadelphia Flyers on Sunday with a lower-body injury.