Teravainen cut it to 3-1 at 14:27 on a backhand in front off a centering pass from Bedard on the rush.
Foligno made it 3-2 at 4:48 of the third period, tipping in a shot from Alex Vlasic.
"They just got to their faster than we did in the first, and then honestly, I thought we took over," said Foligno, the Blackhawks captain. "The chances that we had ... they're going to get their opportunities, they're a skilled team, but I thought for the most part we carried the play and really deserved to equalize the game. So, that's the disappointing part. It's an area we need to address. We just need to make sure we start right."
Guenther extended it to 4-2 with 42 seconds remaining, scoring his second of the game into an empty net after recovering the rebound of Cooley’s long shot.
Lawson Crouse scored on a redirection at 19:38 for the 5-2 final.
“Every team wants to get off to a good start,” Keller said. “This is the best league in the world and you can't take nights off. So, it's great to get the win and now we turn the page and focus on the next game.”
NOTES: Keller became the first captain to score in a franchise's inaugural game since Kelly Buchberger did so for the Atlanta Thrashers on Oct. 2, 1999. … Utah became the eighth team in the NHL’s expansion era (since 1967-68) to win in its inaugural game. The others were the Oakland Seals, Los Angeles Kings, Buffalo Sabres, Calgary Flames, Lightning, Ottawa Senators and Vegas Golden Knights.