Jon Obika says St Mirren are ready to go the distance again on Friday night as they seek to put firm daylight between themselves and relegation rivals Hearts.
The Buddies were forced to battle past Motherwell on penalties to book a William Hill Scottish Cup quarter-final slot on Tuesday night.
Jim Goodwin's men were sitting pretty with a 4-1 half-time lead – only to see Well mount a brave fightback after the break and force extra-time.
But Obika says tiredness will not be an issue as they gear up for another huge game just three days later.
A win in Paisley for Saints will open up a six-point lead over the Gorgie basement boys and frontman Obika said: "We know what's at stake. For us, it's a must-win game.
"But we feel great. The other night is out the way now so Friday is the big one.
"When you go through games like Tuesday's you have to look at the positives, like how even when it went to 4-4 we kept calm and also through the penalties.
"It would have been easy to let our heads go down but we can draw on the confidence we got from beating Motherwell going into Hearts.
"We can't go into Friday with any fear. We know the importance of it and I feel those three points should be ours for sure."
Obika netted a double during regulation time then converted from the spot in the shoot out as his side triumphed at Fir Park.
The former Swindon, Charlton and Yeovil striker now has 10 goals for the season and believes the power of positive thinking has allowed him to transfer his training-ground performances to the first team.
He said: "I feel on the training ground, that's where it all starts.
"You just can't turn it on on match-day, so even if I've had a bad performance I still go into training with a positive attitude.
"It terms of consistency, I think this is the best run I've had. At Swindon, I had a good patch of scoring most games.
"But I feel the confidence is there now and I can score in most games.
"I do enjoy the pressure of scoring goals. You have to back yourself every game, so I'm looking forwards to this part of the season."