LAS VEGAS --- The Vegas Golden Knights had the lead, the momentum and an opportunity to build on their previous victory.

Instead, turnovers and defensive breakdowns turned a promising start into another frustrating finish.

Jack Hughes scored twice, including a dazzling go-ahead goal in the second period, and Arseny Gritsyuk added two goals as the New Jersey Devils defeated the Golden Knights 5-2 on Friday at T-Mobile Arena.

Luke Hughes also scored for the Devils.

The loss spoiled Brayden McNabb’s 900th NHL game, a milestone for the original Golden Knight who assisted on Ivan Barbashev’s first-period goal.

Mark Stone and Barbashev scored for Vegas, which led 2-1 before Gritsyuk tied the game late in the first period.

The Devils took control in the second, while Connor Hellebuyck finished with 19 saves. Adin Hill stopped 26 shots for Vegas.

“We didn’t help ourselves tonight,” Golden Knights coach Ryan Craig said. “Now, New Jersey is a good team and capitalizes on that. It starts with our puck play and turnovers, and then when we didn’t have it, I didn’t think we checked well enough tonight.”

Defenseman Shea Theodore echoed those concerns.

“Our execution wasn’t there. Our physicality wasn’t there,” Theodore said. “We weren’t really getting on the forecheck, getting too many turnovers.”

Jack Hughes made the Golden Knights’ defense look downright foolish with a spectacular individual effort that broke a 2-2 tie in the second period.

Hughes stripped Jack Eichel of the puck in the neutral zone, accelerated toward the Vegas defense, slipped the puck through Stone’s legs to himself and beat Hill.

The sequence exposed the Golden Knights’ poor puck management and defensive positioning in a matter of seconds.

Gritsyuk subsequently extended New Jersey’s lead before Hughes added an empty-netter.

“We just gave them too much space,” Barbashev said of the Devils’ top line.

Vegas has scored just 11 goals over its past five games, including only six at five-on-five, an alarming slowdown for a team that entered Friday with three players - Eichel, Stone and Mitch Marner - combining for 49 points.

The Golden Knights managed only 21 shots against Hellebuyck, struggling to generate sustained pressure after the opening period.

“We didn’t test him enough,” Craig said. “He saw a lot of those pucks. … Just wasn’t enough consistency.”

Craig also acknowledged that execution has slipped over the past 10 days, with poor decision-making and inadequate puck support contributing to the team’s struggles.

Barbashev provided one of Vegas’ few offensive highlights, finishing a slick first-period passing sequence with Marner and McNabb to give the Golden Knights a 2-1 lead.

The goal was Barbashev’s second of the season after entering Friday with 10 points through 14 games. His offensive contributions have remained valuable, but his postgame assessment was particularly revealing.

“I think it’s, to be honest, just on us,” Barbashev said. “We didn’t play well enough today. There’s been some good moments in the first period, but that was it. I think they just shut us down in the second and third.”

The Golden Knights open a four-game road trip Monday in Boston, hoping to correct the defensive lapses and inconsistent execution that have plagued them.

Craig said the team would practice Saturday before heading east, emphasizing the importance of staying together.

“Are we going to stay together?” Craig asked. “Are we going to continue to do the right things to work on our execution?”

Vegas Golden Knights goaltender Adin Hill (33) reaches for the puck with his stick against the New Jersey Devils during the second period at T-Mobile Arena.