"We're not making any changes. That's ridiculous," Johnson said. "We're not going to do that. He's had two games this year."
Johnson's vote of confidence comes two days after the Tigers suffered an embarrassing 47-3 loss to Arkansas State in which Red Wolves coach Hugh Freeze inserted his second- and third-teams just after halftime.
In their first two games this season, the Tigers have given up over 600 yards of offense and yielded an average of 53 points per game.
"We've got to get football going. Larry knows it, I know it," Johnson said. "No one's more disappointed in the last two weekends than I am. That was just terrible. We're the first to admit it.
"We're going to work harder. There's no other way of getting around it. We've got to continue to get this program built and we're going to do so."
The U of M's 44-point loss to the Red Wolves was the biggest loss for either team in the history of the series, which dates back to 1915.
The Tigers (0-2) have not won a game since a Sept. 18, 2010 24-17 victory against MTSU.
"We know what we need to do," Johnson said. "We're all pushing and pulling and in this thing together. … We're going to spend more time and effort than ever before on it and try to get this thing going."
Porter said he's aware of the pressure mounting around him and that he understands the concern.
"There should be frustration based on the way that we're playing," Porter said. "I share the same frustration. I expect probably more than what people are expecting out of us now. The frustration is there, and it's deserved."
Porter said he and Johnson have had numerous discussions about his job security, among other things.
"Certainly we always talk about the direction of this program. We all have concerns," Porter said. "The one thing that's obvious is that we're playing a bad brand of football right now. We need to get better. We have addressed, probably, what the issues are and we're looking forward to getting them resolved." The Tigers will face Division I-AA Austin Peay on Saturday.