Cameroon lost 1-0 to Japan and Denmark were beaten 2-0 by the Netherlands in their opening games on Monday and both sides desperately need a win at Pretoria's Loftus Versfeld stadium to have a realistic hope of making the second round.
Cameroon's players are especially unhappy because Frenchman Le Guen omitted seasoned campaigners like defender Rigobert Song and Geremi and midfielder Alexandre Song from the Japan game.
"What we have seen in recent games, which we think is unfortunate, is that many young fresh players have been introduced into the team at the expense of experienced ones," midfielder Achille Emana told reporters on Thursday.
"They cannot withstand the sort of pressure that comes with playing in big tournaments such as the World Cup," he noted. "That is why we are appealing to the coach to review the lineup for Saturday's game against Denmark."
Le Guen has not spoken to the media since Monday's loss and was conspicuous by his absence at Thursday's news conference.
"More often than not I am not fielded in my right position. I'm made to chase the ball all over the field. And, in that case, how do you expect me to be effective?" he said.
Including Monday's defeat, Cameroon have gone eight matches without a win and key striker Samuel Eto'o told reporters on Monday they needed to keep the faith.
"We played a good match from the beginning to the end. The Japanese had only one chance and they scored. We can't make any more errors and now we have to win against Denmark."
Despite losing their opener to the Netherlands, Denmark are ready to capitalise on Cameroon's woes.
"I think that is one of the good things about our team," he told Reuters. "We have a great team spirit - that's what has carried us through. One defeat is not going to bring us down."
