But Wallace, who came off the bench against Namibia to make his World Cup debut, has rejected those claims.
"I don't see any crisis at all at this stage. We've won two matches out of two. We could start thinking about a crisis if we put in another bad performance in against France," said the Ulster player.
"But as things stand we're confident that we can produce a big performance and beat France on Friday."
Wallace reckons playing Six Nations rivals France, who pipped Ireland to the title this year on points difference, will give Ireland the jolt they need to kickstart their World Cup campaign, as more often than not, they seem to up their game when challenged by the top teams.
"With the two weaker nations up first, I think we've been leaving a lot in the locker for the France and Argentina matches. Hopefully we can bring that out and improve on our performances a lot. "I think, at times, the opposition you play brings a better reaction out of you - and a better performance - and hopefully that's what France will do on Friday. I think we're due one," added the 28-year-old.
Meanwhile, Wallace's Ulster and Ireland team-mate Rory Best is remaining positive that Ireland can beat France and guarantee their place in the World Cup quarter-finals, thus giving him a chance of returning to the fray.
The Ulster captain dislocated his thumb in Ireland's 14-10 win over Georgia last weekend and is looking at a lay-off of between two and three weeks, which means if Ireland fail to qualify out of the pool, Best will have played his last game at the 2007 tournament.
"I hope that there is still a bit of play left in me. The X-ray and scan revealed a bit of damage but it is not as damaged as was first feared or as bad as it could have been. It is now a case of icing it regularly to try to get the swelling down," he revealed.
"I will be out for two weeks minimum and I won't be able to judge how close I am to playing until the swelling goes down and the doctor can properly assess the injury.
"It is big disappointment for me, but these things happen and there is no point being down about it, it is not going to heal any quicker."