Joe Schmidt doesn't feel players will be 'spooked' by injury as first squad cull looms
Munster flanker O'Donnell required oxygen on the Millennium Stadium field after suffering a nasty blow in the closing stages of Ireland's 35-21 World Cup warm-up win over Wales.
The 28-year-old should learn his fate in the next few days, but his chances of finding fitness in time for the World Cup could be slim.
Head coach Schmidt has not given up hope on O'Donnell, and insisted Ireland's players will not fear injury across a month of warm-up clashes.
"I don't think any player gets distracted or spooked by injuries," said Schmidt.
"They know, they've been playing the game long enough.
"I think if you're spooked or distracted by something, then you're more at risk, so I think they'll just forge ahead."
Schmidt will cut his squad this week as the August 31 deadline to name his final World Cup 31 edges ever closer.
Ireland face Scotland in Dublin on Saturday, by which time their training squad could be as many as seven men lighter.
Ireland's Kiwi boss anticipates several difficult conversations this week - but vowed that anyone omitted at this stage would not be completely in the cold.
While it would be unlikely for anyone leaving the Ireland squad in the week to force their way back into the final World Cup squad, Schmidt is adamant that remains plausible.
Munster duo Keith Earls and Donnacha Ryan enhanced their World Cup prospects with fine showings as both ended 29 months without Test rugby in a comfortable victory over Wales in Cardiff.
Ireland start their Pool D World Cup campaign against Canada in Cardiff on September 19 and with Schmidt's first serious squad cull on the cards, that tie inches ever more into overall consciousness.
"I don't think they're ever completely out of the picture, because there can be injuries and there can be illnesses," said Schmidt.
"Selection gets harder and harder if guys keep putting their hands up, and that's part of the selection conundrum that does make it a headache, but it's the headache we want to be honest.
"We don't want something to be clear and obvious because someone hasn't performed: we want to make decisions because two or three players have competed for the same spot."