England will warm up for their $20m (£10m) showdown with the Stanford Super Stars later this year by playing the winners of this weekend's Twenty20 Cup.
The game is one of six matches in an expanded Stanford Super Series event, which is being held in the Caribbean.
England and the Twenty20 Cup winners will also face regional Twenty20 champions Trinidad & Tobago as well as the Stanford Super Stars.
Essex, Kent, Middlesex and Durham meet in Twenty20 finals day on Saturday.
Whichever team comes out on top will face Trinidad & Tobago on 27 October, with the winners of that match pocketing as much as $300,000 (£150,000).
Both sides are guaranteed £100,000, with a further $180,000 going to the winners and $20,000 for the man of the match.
The Twenty20 Cup finalists are already scheduled to take part in the planned Champions League, some time in the autumn.
Although details have yet to be finalised, David Collier, chief executive of the England and Wales Cricket Board, said he was confident there would be no clash and that the Champions League would still go ahead.
"We've had discussions during the week, I think it's well known there are some differences about rules and regulations which still have to be ironed out," he said.
"But certainly, we are hoping for two days in the sun, not just one.
"This (Stanford) game is obviously a great game for the counties to go to, but we're also hoping they will be representing us in the Champions League as well.
"When we made the first announcement of the Twenty20 for $20m game, we said this was something we wanted to percolate down to grassroots, not only in England and Wales but also in the West Indies and I think this announcement shows how this is starting to happen.
"It demonstrates how strong our county game is, and it's a great incentive for the winners at the Rose Bowl, to go out to Antigua and take on Trinidad and Tobago."
West Indies legend Richie Richardson added: "It's going to create interest and enthusiasm that's been lacking in West Indies cricket."
England have agreed to play a total of five winner-takes-all Twenty20 matches against Stanford Super Stars after signing a deal with Texas-born businessman Sir Allen Stanford.
The first match will take place on 1 November at Sir Allen's cricket ground in Antigua.
Winning players will receive £500,000 each, with another £1m split between the rest of the squad and coaches.
The remaining £3.5m will be divided between the West Indies and England and Wales Cricket Boards.
It is believed to be the richest team prize for a single sporting match.
Stanford Super Series schedule:
25 Oct Stanford Super Stars v Trinidad & Tobago
26 Oct England v Twenty20 Champions
27 Oct Trinidad & Tobago v Twenty20 champions
28 Oct England v Trinidad & Tobago
29 Oct Stanford Super Stars v Twenty20 champions
30 Oct Rest day
31 Oct Legends Beach Cricket match
1 Nov Stanford Super Stars v England
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