(Reuters) - The name of the new NHL franchise and first major professional sports team based in the U.S. gambling capital of Las Vegas was revealed as the 'Vegas Golden Knights' in a glitzy, though glitch-marred, launch on Tuesday.

A video meant to build up to the unveiling failed to run properly at the Toshiba Plaza outside their new T-Mobile Arena, leaving owner Bill Foley and NHL Commissioner Gary Bettman stalling for time as technicians tried to fix the problem.

When that failed, they abandoned the video and did a countdown to presenting the team name and logo.

When the name was revealed above the logo of a knight's helmet with a "V" formed in the face of it, fireworks were set off and confetti fell on the cheering crowd.

"I guarantee you we will be better in the rink," shouted majority owner Foley, making light of the video problems.

Five months ago, the National Hockey League decided to roll the dice on expanding to Las Vegas as its 31st franchise, and the first expansion team since 2000 when Columbus and Minnesota were added.

The Golden Knights will begin play in the 2017-18 season.

"We believe in this market," said Commissioner Bettman. "This is a great town. We know everybody here has been hoping for a professional sports team. We're thrilled it's hockey.

"We think by having Las Vegas in the league, it makes the league and hockey stronger. Las Vegas has great visibility."

Foley, chairman of U.S. title insurance services provider Fidelity National Financial , gambled a $500 million franchise fee that Las Vegas will support an NHL team.

The team will play out of the T-Mobile Arena, a new multipurpose building on the south end of the famous Las Vegas Strip that can seat 17,500 for ice hockey.

(Reporting by Larry Fine in New York; Editing by Peter Rutherford)