The Bees lost at this stage last season to London rivals Fulham but were in no mood to be denied this time around and were 2-0 up inside 20 minutes.

Ivan Toney’s 10th-minute penalty kick, his 33rd goal of an amazing campaign, opened the scoring, and Brentford’s lead was doubled by Emiliano Marcondes just under 10 minutes later.

Swansea were much improved in the second half, but Jay Fulton’s red card effectively sealed victory for Brentford as they clinched a first promotion to the top flight since 1935.

It ended their 74-year absence from the highest domestic level, having been relegated back in 1947.

Toney had scored all 10 of his previous penalty kicks this season and never looked likely to err after goalkeeper Freddie Woodman felled Bryan Mbeumo.

That was when he was played in by Sergi Canos’ superb reverse pass.

He duly made it 11 from 11 by calmly slotting beyond former Newcastle United team-mate Woodman and into the bottom-left corner.

Toney’s record from the penalty kick spot was the best of any player in England’s top four tiers in all competitions.

Swansea struggled to respond to that early setback and they were soon given a mountain to climb when Mads Rasmussen expertly picked out Marcondes at the end of a counter-attack.

The Dane rifled a fine finish into the bottom-right corner.

And the Bees were almost out of sight as Toney cracked a spectacular volley against the underside of the crossbar.

Woodman was grateful to see the ball bounce on the line and out.

Swansea did stem the tide thereafter and went close in the final minute of normal time in the first half as Andre Ayew sent a header off the top of the bar.

They started the second half by skewing Ayew’s diving header wide from Connor Roberts’ cross.

Jamal Lowe crafted some promising openings for the Swans but Fulton was shown a straight red card for a reckless challenge on Mathias Jensen.

It gave Brentford fans cause to start the celebrations early on a landmark day for the club.

Swansea were looking to end a three-season stay in the second tier following Premier League relegation in 2018, but Brentford will instead make their debut in the division.

They become the 50th different club to grace the league since its inception in 1992.

Their 86 years between promotions to the top-flight is the second-longest gap behind Bradford City, who ended a wait of 91 years in 1999.

Brentford could start the season against the European champions, with games against Manchester City and Chelsea on the horizon.

For Swansea, it is another term in the Championship, with the likes of Peterborough United and Luton Town lying in wait.