The Kings and Nashville Predators were locked in a test of wills Saturday night at Staples Center, when rookie forward Nick Shore was penalized for closing his hand on the puck after a faceoff in his team’s end of the ice at 4 minutes, 43 seconds of the third period.

At the time, it seemed to be a minor gaffe, something the Kings’ superb penalty-killing unit could erase in two swift minutes. In the end, it proved to be their undoing and led to a 2-1 loss to the Predators in front of a sellout crowd of 18,230.

Nashville’s Craig Smith chipped home a rebound for a power-play goal that tied the score at 1-all at 6:37 of the third. Then, only 66 seconds later, Viktor Stalberg was credited with a go-ahead goal that deflected off the stick of Kings defenseman Jake Muzzin and into Jonathan Quick’s net.

The sequence of plays underscored how the Kings’ margin for error is close to zero at this stage of the season. The Kings fell from a playoff position thanks to their loss to the Predators and a victory for the Winnipeg Jets over the Tampa Bay Lightning.

The reigning Stanley Cup champion Kings (33-22-13) trail the Jets (34-23-12) by one point for the second wild-card spot in the Western Conference. The Kings also are two points behind the Calgary Flames (38-26-5) in the fight for third place in the Pacific Division.

“Any game at this time of the year is tough to lose, and the points are important,” Kings forward Dwight King said. “Going into the third (period) when you have a lead, you’d like to finish out the game, but it didn’t go our way.”

Coach Darryl Sutter refused to fault Shore for closing his hand on the puck, which led to Smith’s 22nd goal of the season. Smith pounced on a loose puck near the right goal post and shot it past Quick to end four consecutive games of penalty-killing perfection for the Kings.

“You’ve got to call it,” Sutter said. “It happens three or four times a year.”

Jeff Carter scored the Kings’ only goal, a power-play strike at 7:44 of the first period.

The Kings played without center Jarret Stoll, who suffered what the team told reporters was an upper-body injury during Thursday’s victory over the Vancouver Canucks. They also were without center Anze Kopitar at their morning skate, although for a far different reason.

Kopitar was absent because he was with his wife, Ines, after she gave birth to the couple’s first child, a 7-pound, 2-ounce girl named Neza at 12:38 a.m. Kopitar joined the team for its game against the Predators at Staples Center, however.

“Once you come here, you try to put everything behind you and focus on the game,” Kopitar said. “I wanted to be here for the guys. Ines told me to go play. I, obviously, wanted to, but she said, ‘You’re going to be itching to go, so you might as well go.’”

Stoll’s injury meant Andy Andreoff moved into the lineup for only the third time since playing in back-to-back games in mid-January. It also raised the possibility that the Kings could recall Mike Richards from their American Hockey League team in Manchester, N.H.