A real test for the Chiefs last night, this, and one they passed but only just. Questions remain about why they are struggling to put teams away this season.
After going out to a 22-11 lead, the Chiefs allowed the Force to hit back to within one point with 10 minutes to go.
It was only a dominant scrum in the final few minutes - Ben Tameifuna's introduction made a difference here - which gave them breathing space.
Prop Kieran Longbottom paid the price for his pack's problems when yellow carded.
Liam Messam went close in the final minutes but lost the ball. It was a frustrating finish to a tricky game and the Chiefs were relieved to win it, especially after Sias Ebersohn's long-range penalty attempt which would have won the game for the Force.
After a controversial early try to Force wing Pat Dellit - the forward pass rule again under the spotlight after a suspect transfer from No 8 Ben McCalman - the Chiefs had to work their way into things in the soggy conditions.
It was an impressive response, the home side scoring points each time they entered the Force's territory. But they couldn't go on with it; replacement halfback Alby Mathewson helping spark a comeback from the visitors.
With first-five Gareth Anscombe turning up to Pukekohe's EcoLight Stadium on crutches due to a broken foot bone, Aaron Cruden started once again.
He kicked six from six in the first extended test of his troublesome groin and quadriceps injuries, but he looks like a man who could do with a rest. Anscombe is expected to be out until after the June tests.
Lock Brodie Retallick was his brutish best in close quarters and flanker Sam Cane looked athletic and supremely motivated. Their contributions were highly important in the finish.
After Dellit went over in the corner, the Chiefs' forwards led the way in front of a crowd of about 6000. Retallick's nice touch wide on the right allowed wing Lelia Masaga to go over in the corner - although lock Toby Lynn should have made the tackle - and the Chiefs regained a lead they would not relinquish.
It was another impressive performance from the Force, who have beaten the Crusaders at home, and, remarkably, the Reds in Brisbane. they also held Ewen McKenzie's men to a draw at Nib Stadium last weekend.
With wing Nick Cummins a constant danger and their forwards increasingly good as the match wore on, they were unlucky not to get more out of it. They were also heavily penalised by referee Mike Fraser.
There was an element of frustration in the Force's play in the second half as they struggled to understand Fraser's rulings, and, with Mathewson lifting the tempo, Dellit scored his second wide on the left after a good burst by fellow wing Cummins. Close but not close enough for the Force.
Chiefs 22 (Lelia Masaga try; Aaron Cruden con, 5 pens
Force 21 (Pat Dellit 2 tries; Jayden Hayward con, 3 pens
HT: 19-11APNZ