Ireland full-back Rob Kearney faces a nervous 48-hour wait to find out whether he will be fit to face Italy on Sunday.
British and Irish Lions star Kearney will undergo a scan in Guildford on Monday afternoon to determine the extent of a gluteal strain.
Kearney suffered a heavy blow to the hip on scoring Ireland's fifth try in Sunday's 44-10 World Cup victory over Romania at Wembley.
The 29-year-old will now have everything crossed his World Cup campaign does not suffer a costly hiccup with Ireland closing in on quarter-final qualification.
"Rob may have suffered a gluteal strain and will have a scan in Guildford later today," said Ireland team manager Mick Kearney.
"We're really going to have to wait and see what the results of the scan are like later today, so I'd say it could be 24 to 48 hours before we have a definitive view on whether he'll be available at the weekend or not."
Keith Earls is expected to complete the head-injury protocols on Tuesday after passing a pitchside assessment during Sunday's Wembley clash.
Connacht centre Robbie Henshaw will train fully this week and ought to be restored to the 12 shirt to face Italy after hamstring trouble ruled him out of the World Cup's opening fortnight.
Ulster wing Tommy Bowe admitted Ireland would miss first-choice full-back Kearney should he fail to beat his knock in time to face the Azzurri at the Olympic Stadium on Sunday.
"Seeing Rob coming off is something you don't want to see," said Bowe. "But I'm sure he's confident it's not going to be something too strenuous, so we'll just have to wait and see.
"Fingers crossed he's going to be fine, but it would be a massive disappointment if he missed out. I don't think we'll worry too much until he gets the medical feedback on it, though."
Munster flyer Simon Zebo would be expected to slot in at 15 should Kearney fail to recover quickly enough, with Bowe backing the British and Irish Lions tourist to cope if called in to deputise.
"We'd all back Simon to get the job done, absolutely," said Bowe.
"Simon is pushing Rob hard for his place there at full-back, he's a very exciting player and he showed he's capable of doing the basics very well as well as being able to light it up as well.
"So I think it just shows with the competition for places, if anyone were to drop out of the match squad, we've got guys to come in and put their hand up and do a great job for the team."
Zebo has been granted compassionate leave from the Ireland Rugby World Cup squad after the death of his grandfather and will return tomorrow the IRFU have announced.