Cardiff City fans are preparing for one of the biggest games in the club's history, which could net the club £90m.
Around 40,000 City fans will converge on Wembley for tomorrow's play-off final against Blackpool, with a place in the Premier League at stake.
Good luck messages have flooded in, including several from Wales' top politicians.
"It's going to be life-changing," said the club's Malaysian investor and director Dato' Chan Tien Ghee.
Dato' Chan, known as TG, added: "It's going to be a tremendous time for Wales."
Cardiff City has never played in the Premier League, and has not featured in England's top flight since 1962.
The rewards for success are great, with a win on Saturday said to be worth in the region of £90m to the club, which has endured a number of years of well-documented financial difficulties.
Paul Rawnsley, director of the sports business group at accountancy firm Deloitte, explained: "The winners will benefit from at least £40m of additional revenue in 2010/11, the vast majority of this coming from television income and the rest from higher gate receipts and increased commercial income.
"In addition, even if a club is relegated after one year in the Premier League, parachute payments may be received over the following four seasons of up to £48m.
"In financial terms, this match offers the winning club the most substantial prize in world football.
"It is a prize which provides the opportunity for sound investment and strengthening the foundations of a club for years to come."
For the wider economy in south Wales, a 2003 Cardiff council study estimated that having a Premier League club in the Welsh capital would generate around £10m and create around 400 jobs.
The football club would be among the top 25 businesses in the city.
Good luck messages have been sent to Dave Jones's team by First Minister Carwyn Jones and Welsh Secretary Cheryl Gillan.
"It's a massive weekend for Cardiff football and rugby fans and I'd like to wish both teams all the best luck for their big matches," said Mr Jones.
Mrs Gillan said: "I sincerely hope that come tomorrow, Cardiff will be the first Welsh team to make it to the Premier League."
Boxing star Joe Calzaghe and Lord Kinnock are among the more famous City fans who will attend the game.
Liverpool and England star Steven Gerrard, cousin of Cardiff player Anthony Gerrard, has also revealed he will be rooting for the Bluebirds from England's pre-World Cup high-altitude Austrian training camp.
"We have a good relationship and I will be sending him good luck messages beforehand," he told his club's website.
"I would love nothing better than for him to get to the Premier League."
Fans travelling to the match by road have been made aware of potential delays with plans to close a section of the M4 in Wiltshire from around 2000 BST Saturday night forcing drivers to take a detour on the way home.
The motorway is due to close between junctions 16 and 17, and detours for light vehicles are planned along the B4042 and A429 via Malmesbury, and the A3102, A4 and A350 via Calne and Chippenham for heavy vehicles.
Those making the trip by rail have been warned by police that anti-social or intimidating behaviour will not be tolerated.
British Transport Police announced that extra officers will be on duty on trains and at stations, and alcohol has been banned from services.
Should the Bluebirds triumph at Wembley then an open top bus victory parade will take place in Cardiff on Sunday.
Cardiff council revealed that fans will be invited to greet Dave Jones and his team at Cardiff Bay at 1600 BST.
Lord Mayor of Cardiff, Councillor Keith Hyde, said: "Should the Bluebirds win there will be a lot to celebrate, this is why we have planned a victory parade."
On Friday afternoon Cardiff City ticket office reported that it still had 30 tickets left of the 37,000 allocated.