Willis Halaholo has not been released from Wales camp this week after suffering a gruesome training ground injury.
The hot-stepping centre was due to feature for club side Cardiff this Friday night against Zebre to prove his fitness for national duty against England.
But he has remained at the national side's Vale Resort HQ to be monitored.
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A short statement from the WRU read: "Following a laceration to the eyelid sustained in training on Tuesday, Willis Halaholo will remain with the Wales squad this week for monitoring rather than being released to Cardiff Rugby."
It was due to be his first game in five weeks, having not played since the Blue and Blacks welcomed Harlequins to the Welsh capital.
Halaholo has missed the opening two rounds of the Six Nations with a hamstring problem and this latest injury makes him a significant doubt to start at Twickenham next weekend.
Wales remain optimistic that he will be available for selection for the game against Eddie Jones' side, but whether Wayne Pivac will see fit to select him from the start, having not played for six weeks, is another matter.
It comes as a blow to Pivac, though, as Wales have been lacking in the creativity stakes in the opening rounds of the championship.
Halaholo is the trickiest midfield operator at Pivac's disposal and there were suggestions that a run-out for Cardiff this weekend would put him firmly in the frame to start at Twickenham.
But this latest injury will likely force a rethink, although a place on the bench would not entirely be out of the question next weekend.
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