They also have won four in a row heading into Game 2 on Sunday.
"It's always great when you win the first game, especially back to back, give you a little momentum," Hossa said. "I felt like we did lots of good things today. We know we have to be better [Sunday] and keep doing those things."
Jonathan Quick stopped 34 shots, and Justin Williams scored for Los Angeles, which has won just one of seven road games in the playoffs. The defending Stanley Cup champions got center Jarret Stoll back from a suspected concussion, but their offensive funk continued.
"I think the two guys that scored for them are going to score goals," Kings coach Darryl Sutter said. "We have guys that have to score goals. That's how close it will be."
Los Angeles has scored 27 times in 14 playoff games. The last three have gone to Williams, who was responsible for the Kings' offense in a 2-1 victory over the San Jose Sharks in Game 7 of the second-round series on Tuesday.
"Scoring doesn't simply come from the offensive zone," Williams said. "It comes from being good in your own zone, breaking out together and scoring off the rush. We didn't have enough of that."
The Blackhawks and Kings returned to the ice after surviving strenuous second-round tests.
Top-seeded Chicago stormed back to beat Detroit after trailing 3-1 in the series, winning Game 7 on Brent Seabrook's overtime goal Wednesday night. Fifth-seeded Los Angeles was pushed to the brink of elimination by the Sharks in a series in which the home team won every game.
Bruins 3, Penguins 0 • In Pittsburgh, David Krejci scored two more goals during his torrid postseason and Boston shut down Pittsburgh in the opening game of the Eastern Conference finals.
Nathan Horton added an insurance goal in the third period, and Tuukka Rask stopped 29 shots for the Bruins, who silenced Sidney Crosby and the rest of the NHL's top-scoring team.
Pittsburgh came in averaging a league-high 4.27 goals in the playoffs but couldn't solve Rask. The Penguins hit the post six times and seemed a little bit off following an eight-day break between rounds.
P Conference finals
• Chicago 2, L.A. 1
Blackhawks lead serie 1-0
• Boston 3, Pittsburgh 0,
Bruins lead series 1-0
• Los Angeles at Chicago, 6 p.m., NBCSN
• Boston at Pittsburgh, 6 p.m.