Leinster have a long list of injury concerns involving Ireland internationals, with Luke McGrath's knee ligament injury the latest among them.
Leinster and the Scarlets maintained their impressive Pro14 form on Saturday, the latter bouncing back from some poor European results.
Cooney was a high-profile omission from Andy Farrell's original 35-man squad, missing out on a call-up alongside Leinster No 9 Luke McGrath.
Ireland were blown away in the quarter-finals by New Zealand, yet reserve scrum-half Luke McGrath insists that their tame elimination will not taint the legacy of departing coach Joe Schmidt.
Kieran Marmion, Bundee Aki and Luke McGrath crossed to give Ireland a largely unconvincing win over Argentina.
Scotland international Adam Hastings was sent-off as Glasgow lost 40-21 at reigning Guinness PRO14 champions Leinster.
In now looks likely that Farrell will go with a familiar looking team for Saturday's game, as Ireland look to get back to winning ways.
The 21-year-old out-half has been one of Leinster's most impressive performers in the Guinness Pro14 this season.