Newcastle has so far struggled to combine performances and results in the Premier League this season and lost its European opener at home to Barcelona – a game in which Gordon scored a late consolation.

But it all came together for Eddie Howe's men in Brussels as Gordon, whose own campaign has endured a frustrating start after a red card against Liverpool, played a starring role.

Nick Woltemade opened the scoring after 17 minutes with a flick so delicate his goal was initially awarded to Sandro Tonali, whose shot appeared to have deflected in off Kevin Mac Allister, rather than the Germany striker.

Then Gordon's first spot-kick two minutes before half-time ensured some comfort for the visitors at the break, with Anthony Elanga fouled just inside the area and his fellow winger sweeping in from 12 yards.

It was Gordon's own cross that prompted the second penalty decision, awarded for Fedde Leysen's handball after a VAR review, and another composed finish was followed by a breakaway goal from substitute Harvey Barnes that saw this scoreline eclipse the 4-1 win over Paris Saint-Germain in 2023.

Newcastle boss Eddie Howe praised his side for taking a big step in the right direction.

"That was exactly what we would have wanted, especially after the Arsenal ending," Howe said.

"That was a big response from the players, because that was a painful way to lose that game.

"The players had to look deep within themselves and come out fighting again. That's what we do best."

Goals have been a particular issue or Newcastle, but there were signs of confidence returning to Howe's attackers in this match.

Woltemade has three goals in four starts and became the first Newcastle player to net on both his first Premier League start and first UEFA Champions League start for the club.

Meanwhile, Gordon, who scored in the prior defeat to Barcelona, became just the third Newcastle player to net in consecutive UEFA Champions League matches.

"Hopefully it helps us when we return to the Premier League, because we've been waiting for a performance like that really," Howe said.

"We looked like we could score at any moment.

"It wasn't a perfect performance, there's things we could improve, but it was a big step in the right direction.

"It's an important stage as well in the [UEFA] Champions League, because we have to start well. These competitions are so high, the demands are so big on us, that if we're slow starters, we could leave ourselves too much to do.

"I certainly leave in a much healthier, positive frame of mind and looking forward to the next game."

Union SG coach Sebastien Pocognli said: "I'm proud of my team. They fought and even at 3-0 down they didn't give up. Newcastle were just on another level."

In the other early match of the day, Qarabag continued its superb start to the campaign by beating FC Copenhagen 2-0 at home.