New Kettering boss Mark Stimson got off to the dream start as his side took all three points at Lincoln.
The Imps dominated the first half but Brad Barraclough, Alan Power and Jamie Taylor were unable to make the most of good chances.
The visitors took the lead after the break through Jean-Paul Marna's strike.
Jean-Francois Christophe fouled Adam Cunnington in the area, Moses Ashikodi slotting home the penalty before Christophe saw red in the final minute.
Stimson has not been officially confirmed as Poppies manager yet but took charge of the side.
VIEWS FROM THE DRESSING ROOM
Kettering Town manager Mark Stimson told BBC Radio Northampton:
"Personally it was fantastic to be back in the hot seat.
"At the moment I haven't signed a contract. My contract is with the LMA who represent me.
"We'll speak next week (with chairman Imraan Ladak) to make sure everything is right and he wants me to have a lot of control on the football side of things."
Lincoln City: Anyon, Christophe, Gowling, Nelson, Nutter, Russell, Power, Fuseini, Barraclough, Taylor (McCallum 68), Smith (Perry 68).
Subs Not Used: Watts, Hone, Nicolau.
Sent Off: Christophe (90).
Kettering: Walker, Phil Ifil, Jerel Ifil, Taft ,Davis, Bridges (Cunnington 55) ,Koo-Boothe, Clapham (Meechan 55), Ashikodi (Sekajja 86), Noubissie, Marna.
Subs Not Used: Haxhia, Navarro.
Booked: Taft, Jerel Ifil.
Goals: Marna 63, Ashikodi 82 pen.
Ref: Nick Kinseley (Essex).