The Portuguese retained slim chances of progressing after scoring a late equaliser in a pulsating 2-2 draw against the Americans in the Amazonia arena on Sunday.
"Ronaldo was fit, he played the full 90 minutes and he didn't seem to have any problem," a poker-faced Bento told a news conference.
"This is a delicate moment for all our players. They are all a bit sad now and this is not the moment to criticise individuals.
"Criticise me as a coach if you will, we had a chance to get a result here today, we didn't but we have to move on and try to beat Ghana."
Bento was asked if he believed United States coach Juergen Klinsmann's vow to play all out for a win against his native Germany even though a draw would send both sides through at the expense of Portugal and Ghana.
"In my entire career as a player and coach, I have never been suspicious about my colleagues playing for a draw," he said.
"Our obligation is to beat Ghana and although our chances are slim even if we do, we will maintain our professional standards until the very last minute."
All four teams are still in the reckoning with a myriad of potential scenarios, but Portugal can only advance if they beat the Ghanaians and hope the United States v Germany result goes their way.
Substitute Silvestre Varela levelled at the death after a subdued Ronaldo delivered a cross into the penalty area but Bento said neither the world player of the year nor any of his team mates had struggled in the humid conditions.
"We were fine physically, it was more the mental aspect that determined the course of the game," he said.
"We were a goal up and then fell behind. In the end we got an equaliser that leaves us in with a mathematical chance to progress.
"We dominated the first 45 minutes and should have scored more goals but the situation changed in the second half. We never lost control of the match although we didn't dominate the whole game and failed to contain their right wing.
"The second U.S. goal came through our mistakes and in the end I guess a draw was a fair result although it left us in a very difficult situation."
- Sports & Recreation
- Cristiano Ronaldo