Leigh will feel justice was done after dominating this high-octane affair, aside from when Leutele was binned for a challenge on Jack Welsby on 53 minutes.
Elsewhere they won the physical battle convincingly, with hooker Edwin Ipape setting the tone of a ferocious display without the ball.
In possession they shaded it as well, John Asiata, with a full-stretch fingertip grounding confirmed by video referee Ben Thaler after 21 minutes, giving the hosts the lead.
Then Leutele finished off a superb move through Lachlan Lam and Matt Moylan just before half-time to give Adrian Lam’s side a comfortable lead at the break.
Yet Saints, stung after an early try by Tommy Makinson was ruled out for an obstruction, came roaring back when the Leopards went a man down.
First Makinson touched down in the right corner on 59 minutes and Morgan Knowles got on the end of a high kick from Jonny Lomax three minutes later.
But, after doing the hard work to draw level, Saints were stunned by Charnley, who finished off a fluent move getting over in the left corner to retake the lead.
With six minutes to go, Makinson’s attempt to offload off the floor gifted a penalty to the home side which Moylan calmly slotted over to wrap up their fifth-placed finish.
