The Cornhuskers, picked to finish last in the Big Ten, started fast and never trailed against an Eagles team that was the darling of the NCAA tournament last March.
Shields was 8 of 13 from the field and made all 12 of his free throws. His makes and attempts from the line were career highs. He also led the Huskers with six rebounds.
Jamail Jones had 17 points and eight rebounds, Bernard Thompson scored 12 points and Filip Cvjeticanin 10 for Florida Gulf Coast, which is favored to win the Atlantic Sun Conference.
The Huskers played without top returning scorer Ray Gallegos, who was suspended for the first two games because of a violation of team rules.
Nebraska opened the $179 million downtown arena in style. Tommy Lee, the Motley Crue drummer who filmed a reality TV show on campus in 2005, made an appearance. So did the marching band, whose members squeezed onto the court to play the fight song before the Huskers entered to a Bon Jovi pump-up video.
The Huskers fed off the opening-night energy and crowd of 15,119. Nebraska hit three of their five 3-pointers in the first three minutes, with Petteway making one right after the opening tipoff.
The Eagles became known as "Dunk City" during the NCAA tournament, but they had nary a slam against the Huskers. Nebraska had two. Shields flushed a backdoor pass from David Rivers for the Huskers' first double-digit lead. Rivers had a dunk a couple minutes later, and Shields' reverse layup finished an 11-2 run that put the Huskers up 29-15.
Benny Parker came off the bench to give the Huskers a lift early in the second half with a three-point play, fast-break layup and steal and layup in succession. Petteway, a transfer from Texas Tech, followed with a basket to finish a 10-0 run that made it 55-32.
The lead grew to 33 points with under 6 minutes left.
Florida Gulf Coast, which lost 51-50 in Lincoln two years ago, fell to 0-7 all-time against Big Ten opponents.
The Eagles captured the imagination of the country last March, upsetting Georgetown and San Diego State to become the first No. 15 seed to reach the NCAA Sweet 16. Andy Enfield suddenly was the nation's hot coach, and he was swooped up by Southern California.
Joe Dooley, an assistant at Kansas the last 10 seasons, was hired in April and inherited a team that brought back four starters from its 26-win team.
Only three of those starters and a total of seven scholarship players were available Friday. Eric McKnight, who started 34 games, is suspended for the first six games for violating team rules.
The game was the second half of a doubleheader to mark the grand opening of the arena. The 17th-ranked Nebraska women defeated UCLA 77-49 in front of an afternoon crowd of 9,750.