The Kings appeared to tie the game on a goal by Quinton Byfield in the second period, but video review determined the play was offside and the goal was overturned following a challenge by the Lightning.
"[Jacob Moverare] was over with possession...his skates...when he released the pass to [Byfield] the puck wasn't fully over the blue line yet," Los Angeles coach Jim Hiller said. "A couple inches...millimeters maybe. We needed one. That was a big goal. What do you do, right? That's the rules. We just missed it."
Hagel made it 2-0 at 15:39 of the third period after sending a pass to a streaking Kucherov for a breakaway. Rittich made the save on the breakaway, but Hagel beat Drew Doughty to the loose puck and scored on the rebound.
"We stuck with it, we had tons of chances, and the score maybe could have been a little bit different," Hagel said. "But we ended up getting one late. I think it shows a lot of grit by our team to stick with it and kind of put that frustration behind you."
Cirelli scored an empty-net short-handed goal at 18:43 for the 3-0 final with Rittich pulled on the power-play for a 6-on-4 advantage.
"I don't think our confidence is there right now," Spence said. "Obviously we have some chances to score some goals; we're not capitalizing on our chances. At the end of the day, we're not playing well right now. We just have to reset, forget about tonight and get ready for [the Carolina Hurricanes on Saturday]."
NOTES: Kings defenseman Mikey Anderson left the game in the first period with an upper-body injury and did not return. Hiller said he was concerned about Anderson's injury but expects him to travel to Carolina. ...Lightning goalie Jonas Johansson was scratched with a lower-body injury. Matt Tomkins was recalled from Syracuse and dressed as the backup. … Doughty was minus-2 in 27:43, his second game back from a broken ankle sustained during the preseason.