Defeat by 13 or more points would see Dewsbury relegated to Co-operative Championship One for 2012, but a solitary bonus point could be enough to avoid the drop if Hunslet and York suffer defeats later in the week.
Jowitt said: “We need to win. If we do win, that could pretty much ensure us staying up – although it depends on how Hunslet and York get on. But a win would pile the pressure on those two.
“However, we’ve got the toughest challenge of all in having to face Leigh. They’re the most consistent side in this division and they’re the real big guns.”
He added: “It’s all about keeping the lads focussed on their jobs. We can’t worry about York or Hunslet, we’ve just got to worry about ourselves.
“There’s been a buzz about training and there’s confidence in the lads – hopefully now we can take that to the field on Thursday.”
Centurions’ squad includes dual-registered Tom Armstrong, with assistant coach Paul Rowley warning Leigh’s players to expect a confrontational battle.
Rowley said: “If Dewsbury do go down, they’ll go down fighting. It’s a tight pitch and it will be a physical battle. They’ve been inconsistent all year, which makes them dangerous because you don’t know what you’re going to get.
“A win for ourselves would keep a bit of pressure on Featherstone, but either way we’re playing Featherstone in the play-offs. We’ll just focus on our own systems and try to make sure we perform the best we can.”