Saints started the second half with the same intent as the first but Exeter’s defence held out for 14 phases in and around their line in the opening five minutes in a stand reminiscent of the end of their semi-final win at Bath last week.
Rory Hutchinson had a try ruled out for a knock-on two minutes later as the table-toppers looked to assert themselves.
But the momentum swung when Kemeny was sin-binned for a 51st-minute head to head clash with Jenkins, and a few phases after Exeter had kicked the resulting penalty for a close-range lineout the Wales lock forced his way in.
Saints were dealt a further blow when England scrum-half Alex Mitchell – on as a first-half replacement for the injured McParland – dropped the ball under a challenge from Ridl as he went over the Exeter line.
However, in the aftermath replays showed Jenkins had put in a dangerous challenge on Furbank and he was sent to the sin-bin with 23 minutes left.
Saints dominated the ball with the extra man and were rewarded when Hendy dived over in the right corner after a fine flowing move across the field.
It proved to be the hammer blow for Exeter’s hopes as Saints reclaimed the crown they lost to Bath 12 months ago.
More to follow.
Northampton: Furbank (c); Freeman, Litchfield, Hutchinson, Hendy; Smith, McParland; Iyogun, Langdon, Millar Mills; Coles, Prowse, Kemeny, Pearson, Pollock.
Replacements: Wright, Fischetti, Green, Van der Mescht, Lockett, Chick, Mitchell, Dingwall.
Yellow card: Kemeny (51)
Exeter: Woodburn; Feyi-Waboso, Slade, Ikitau, Ridl; Skinner, Varney; Sio, Norey, Iosefa-Scott; Jenkins (c), Zambonin, Hooper, Roots, Fisilau.
Replacements: Dweba, Burger, Tchumbadze, Tshiunza, Vintcent, James, Cairns, Haydon-Wood.
Yellow card: Jenkins (57)
Referee: Matthew Carley.