Giovanni Trapattoni's side face Sweden in Dublin on Friday before travelling to Austria next Tuesday with all three sides locked on 11 points together in Group C.
Trapattoni has targeted four points from the two games and Keane admits it is vital they do not lose against Sweden.
"It's certainly a game we are targeting to get the three points," said Keane.
"These two matches are make or break, so this is it now, these are the games that the players have been looking forward to.
"We kind of knew it was going to come down to this between ourselves, Sweden and Austria, so it's a game we can't afford to lose, no question about that.
"People are talking about going in and trying to get a draw - it's very hard for any player to do that. You go into every game trying to get the three points. But the most important thing is not to lose."
Rep. Ireland v Sweden is live on Sky Sports 2HD at 7.30pm