Steven Naismith rejects talk of unrest at Hearts and insists players are fully behind Daniel Stendel
Rejecting talk of dressing-room unrest, Naismith said the players are working together in the ongoing battle against relegation.
Saturday's 2-2 draw with Hamilton at Tynecastle Park leaves Hearts bottom of the Premiership by a point, attaching extra importance to the trip to Paisley.
St Mirren are three points better off in tenth place. "It's a must-not-lose game. That's the bigger issue here," Naismith told Hearts TV.
"We've got to have a much better performance than the weekend and be solid defensively, and then be comfortable and confident enough on the ball to create chances. It's a game we are firmly going into hoping to win.
"The result at the weekend is one of those shock results that you want to use to spark a reaction. I'm sure this week that's what we will be doing."
Asked about a media report suggesting players cannot understand Stendel and his tactics, Naismith replied: "I was surprised to see it. If I'm honest, it's a lot of rubbish.
"In terms of the manager's work, we had a good period during the winter break which was crystal clear for everybody to understand. The manager's English is pretty good. The bottom line is that it's been individual errors in one player, maybe being out of position or made the wrong decision, which has cost us in these games.
"The second half at the weekend shows that we are still fighting. We do want to get back in this and get something from the game. We did that. We have had a lot of problems recently but we're fighting as one group to push forward and get out of this mess.
"We've known over the weeks that that is the only way to get out of this. If anybody in the group - whether it be coach, player, staff - goes their own way, then they will be excluded from the group. It's as simple as that. It's not as if one person is going to make fortunes turn round for us."
The 33-year-old is desperate for his team to put together a sequence of victories to show they can remain in the top flight. He reiterated that is only possible with complete unity.
"That's the only way it can go. First of all, we need a few games where we come away with three points. That probably releases a lot of the pressure surrounding the situation. Then we can look to build on that.
"We are going to go into a period where we are playing against teams all round about you. Although it's only the three points, psychologically it is a bit more in these games. We've got to take responsibility for that. Go into these games confident, play the way we can play and come out with the points."
The weekend draw left the Hearts squad upset after failing to record win which would have lifted them off the bottom of the league. "Frustration and anger," said Naismith. "The anger is that it's a home game against a team that is round about you in the league. You want to go and stamp your authority on the game and then go on to try and win.
"When we are giving up cheap goals, as we are, it changes the whole complex of the game. You end up having to take a lot more risks. At the end of the day, we did that and got a point out of it but that's not really the result we were hoping for before the game, or what we expect from us as a squad."
The skipper again paid tribute to the Hearts supporters, who are expected to travel to Paisley in their numbers.
"It's important but something I've already mentioned to the players is that you can't take that kind of support for granted," explained Naismith.
"It can be a tough place to play here [at Tynecastle] but at this moment in time the fans are firmly behind us. There is an expectation there and it's got to be there for a club like this.
"Now it's the players' opportunity in these games to come out and show they are up for taking on that responsibility - and becoming a player who does well for this club, and maybe more beyond that."