Joe McCarthy and Mack Hansen have emerged as doubts for the Lions' second test against Australia on Saturday.
Both players are managing foot injuries, and sat out training in Melbourne earlier today.
Their Ireland teammates Jamie Osborne and Thomas Clarkson are included in the squad to play tomorrow.
Osborne is one of four Irish starters to take on the First Nations and Pasifika side.
The others are Finlay Bealham, James Ryan and Josh van der Flier while Clarkson is on the bench with the fit-again Garry Ringrose.
World Rugby says it stands "in solidarity" with England - after upholding complaints of racist abuse during their Test match against Argentina earlier this month.
But the governing body says it's been unable to identify the individuals responsible.
The incident happened when England replacements were warming up during the first half in San Juan.
World Rugby says it will work the Argentina rugby board to educate fans.
