The opening three goals of the contest arrived in an extraordinary four-minute period in the first half, with Mario Lemina heading in a Pablo Sarabia delivery for the second consecutive game to give Wolves the perfect start.

O'Neil's side remarkably doubled their lead just 12 seconds after the hosts restarted play, as Hwang raced on to a poor backpass from his former team-mate Nathan Collins to round home goalkeeper Mark Flekken and tap into an empty net.

Brentford responded with a goal of their own within two minutes when Yoane Wissa lashed a right-foot effort past Wolves stopper Jose Sa from Neal Maupay's deft flick over the visiting defence.

But having seemingly subdued the visitors, another defensive lapse from the hosts presented Wolves with their third goal and Hwang with his 10th of the season.

The South Korea forward was left completely unmarked as he collected Toti Gomes' powerful header forward and finished with aplomb - superbly lifting the ball over the onrushing Ethan Pinnock before placing it past Flekken.

With Brentford unable to convert several excellent opportunities to reduce the deficit, Jean-Ricner Bellegarde, who replaced Hwang in first-half stoppage time, rounded off the scoring late on for the visitors, with the error-prone Collins again culpable on a miserable night for the hosts.

"We were very clinical," said O'Neil. "You don't win by that score too many times away in the Premier League, so it's one for the fans to enjoy.

"Brentford were aggressive. We didn't have loads of control but we had big opportunities to go one-on-one and we caused them problems."

Bees' worries build

In his pre-match comments, Brentford boss Thomas Frank said he expected to see his side "come out flying" after a 10-day gap since their last game, the unfortunate home loss to Aston Villa.

But if anything, their inaction, due to Manchester City's involvement in the Club World Cup, had the opposite effect.

They allowed a clinical Wolves side, who had lost their four previous matches on their travels and their last 14 in London, to take complete control in the opening half an hour.

Both of Hwang's goals could be classed as belated Christmas gifts from the Brentford backline, while Bellegarde's also came courtesy of a dreadful Collins pass straight to Matheus Cunha on the edge of his own penalty area.

Worryingly for Frank, his team's sixth defeat in seven games was also the first time they have shipped four at home in the Premier League.

And on this evidence, he will need some players to return soon, with the losses of the suspended Ivan Toney and injured Bryan Mbeumo in particular sorely felt in the final third.

"When it rains it pours," said Frank. "This moment in time it doesn't go our way.

"We had so many promising attacks and big chances that could have given us a little bit. But it didn't. We performed well, we just made too many big mistakes that killed the game."

He said they did not deserve the scoreline, but added: "We made two big mistakes, which doesn't help us, and we conceded two other goals we definitely could avoid. But let's give a bit of credit to Wolves."

Resurgent Wolves

While Wolves have beaten the likes of Manchester City and Chelsea at Molineux, they had struggled to replicate those sorts of performances on the road.

But if they continue in this vein, it would not be unreasonable for O'Neil and his team to target a European spot.

They will, though, have to manage the loss of Hwang for the Asia Cup, with his growing stature and assuredness in front of goal a huge asset.

"He's a dream. I just write his name down and let him get on with it," O'Neil told Amazon Prime.

"When it falls to him at the goal, I get really relaxed because he's got fantastic quality. He shows it all the time in training."

O'Neil will at least be heartened that Hwang's absence will be offset by the return of Portuguese playmaker Pedro Neto, who was on the Wolves bench after a two-month absence with a hamstring injury.