Fukufuji, the first native of Japan to play in the NHL, replaced Barry Brust to start the third period. He faced five shots on goal but gave up Wideman's goal 7 minutes 32 seconds into the period that gave the Blues a 6-4 lead.
"I was so nervous," he said. "But I was very excited too."
Fukufuji, 24, was recalled Friday on an emergency basis after Mathieu Garon was put on injured reserve because of a finger injury. Fukufuji became the first native of Japan to dress for a league game, Dec. 16 against Dallas in another emergency stint.
"I thought we played a heck of a game," Coach Marc Crawford said. "We had 90% of our players who played their hearts out tonight. We were deserving of more than we got."
Wideman assisted on a second-period goal by Keith Tkachuk and on Martin Rucinsky's score in the first -- both on the power play.
The Blues took the lead, 5-4, on Doug Weight's goal late in the second period, his fifth. Weight assisted on Rucinsky's goal and helped set up Wideman's score.
Rob Blake's power-play goal with 5:12 made it 6-5.
Blake gave the Kings a brief 3-2 lead when he scored 97 seconds into the second period.
Michael Cammalleri started the scoring 3:31 into the game.