The fact that Celtic scored nine goals at the weekend has concentrated the minds of Jefferies' players, whom the manager expects to show as much commitment against the Glasgow side as they did against Hibernian in their 2-0 win at Easter Road.
"Our feet are on the ground because we're playing against a very good team on a high, following their performance on Saturday," Jefferies said.
"It's the perfect game for us. No disrespect to others but, if it's a lesser team, you go in thinking maybe it's a foregone conclusion, you take things for granted and things are a bit flat. There will be a great atmosphere for this one, the crowd will be behind us, so it should be a cracker.
"I don't think there's any doubt that we're buzzing after the derby win, although we've had a few wounded in there. They were up for a battle and, when you saw the number of knocks we had the following morning, it proved that.
"The players knew my feelings immediately after the Kilmarnock game," he continued, referring to Hearts' 3-0 home defeat the previous Sunday. "They came in for some heavy words on the Monday morning - so, credit where it's due, I called them in (on Monday] to say they'd taken the stick after the Killie game, now they deserved the praise.
"We won't win every game, but we'll be hard to beat. You can accept not winning, but you can't accept a lack of commitment to the cause."
As well as expecting his own team to be on their toes, Jefferies said he was certain Celtic would not be seduced by complacency either following that 9-0 victory over Aberdeen. "I'm not sure you get Celtic or Rangers in complacent mood ever. It's ground into them, the levels expected from first minute to last.
"They're under pressure to win every game, every week. So I don't see it being an issue for them. They're used to winning games, and if they're on a massive high, so should we be after a great performance against our big rivals."
Jefferies expects striker Kevin Kyle to be fit for this evening's game after being treated for a variety of knocks and bruises following the derby. Winger Suso Santana, an unused substitute at Easter Road, should also be available, but has a continuing knee problem that the manager expects will need treatment sooner rather than later. David Templeton is doubtful, however, after taking a heavy knock in the first half of Sunday's game.