Coleman suffered a double leg-break in Ireland's World Cup qualifier against Wales on Friday after finding himself on the receiving end of a hefty Neil Taylor tackle and he expected to be out of action until at least 2018.
The Boys in Green were held to a 0-0 draw at the Aviva Stadium, meaning they remain unbeaten in their quest for qualification. However, the result sees them drop off top spot in Group D, though they are still level with leaders Serbia on 11 points.
Reflecting on the horror injury suffered by the Everton defender, O'Shea is adamant that Martin O'Neill's team must now make sure they have a place in the tournament next year.
"It's on your mind without a doubt, then the game kind of naturally takes over if you know what I mean," the Sunderland defender told Newstalk.
"It's obviously such an important game to win, if we had gotten the three points, not that it's going to make up for Seamus, but it would be fitting for him if we were able to get a win.
"But now we have to, for Seamus, get to that World Cup. For everyone in the country, but for him now after what has happened it will be a big thing, you know?"
Football's world governing body FIFA are set to cover Coleman's salary for the duration of his rehabilitation as part of their club protection scheme.