Nicky Reid netted a second half winner in midweek for his 19th of the season as Penicuik took all three points in a 2-1 win over Dunbar United to stay top.
Paul Tansey was forced off at half-time with a knock, with his replacement, veteran striker Lumbert Kateleza, making a big impression after the interval.
“The last 20 minutes was as good as I’ve seen Penicuik play this season to be fair, I was really pleased with that,” said McLeish.
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“Lumbo brought a lot of energy, he’s got a change of pace and he takes the ball and he frightens the life out of people when he’s got it, which creates space for others.
“I’ve got 21 players in the squad and I could play any 11 of them tomorrow, I have that much confidence in them.
‘They are a good bunch and I’m not fazed by putting any of them in, I’ve got kids who can play and older guys who can play.
“I’m not sure where we are going to go with it, all I know is we’ve had a set way of playing pretty much all season and I can’t see that changing too much.
“We are all well aware of what our structure and strategy is, how we will shape up in terms of personnel is still unknown.”
Many are billing tomorrow’s match as a potential title decider, but McLeish says it is too early for such talk.
He added: “It’s another game, it’s three points that’s all it is. It’s hallway through the season for us and that’s it.
“People will be looking at it from the outside going ‘It’s a league decider’ but it’s not, it’s three points that is up for grabs and both teams want them as much as each other.
“It’s an attractive game and It will be a competitive game, it won’t be one team running over the top of the other.”