The IRB have blocked the RFU's repeated bids to have England's opening June Test against New Zealand pushed back a week.
With the match scheduled for June 7th, players involved in the Premiership final on May 31st will be unavailable for selection due to player welfare regulations.
That means England may be without a number of big names, hardly ideal when facing the world's best at their Auckland stronghold.
Were the league's current top two - Saracens and Northampton Saints - to reach the final, the likes of Owen Farrell, the Vunipola brothers, Courtney Lawes, Tom Wood, and Lee Dickson would miss out.
Similarly, third-placed Leicester Tigers' involvement would rule out Manu Tuilagi and Tom Youngs.
RFU Chairman Bill Beaumont claims the IRB's refusal to move the Test centres on a disagreement regarding the start of the June window.
"We made a request to the IRB because they interpreted the weekend of May 31-June 1 as a June weekend, and we maintain it is a May weekend," Beaumont told The Rugby Paper.
"We've tried for some time now to get it changed, but to no avail."
An IRB spokesman hinted the RFU had failed to lodge their complaint in time to have the fixture list altered.
"When the Test schedule was agreed in 2010 the RFU was going through administrative changes. At that time they were asked to respond to the schedule, and that did not happen, so the schedule was drawn up as is," said the spokesman.