"It's been the same at Leinster this season. If you have injuries, you're compromised and have to fight your way through those periods," he told Sky Sports News.
"I certainly sympathise with the recent Irish performances and the results that didn't go their way can be mitigated by the number of key players who were missing.
"Look at the way Munster have recharged themselves recently following the return of key players. I hope that with Ireland we'll have less injuries and give the performances that will meet the expectations of our supporters."
Ireland won just once in the Six Nations this year.