The Colonels had left the door open earlier in the overtime when a bad snap forced them to settle for a field goal that gave them a 38-35 lead.
The two teams had finished their regulation game tied with 28 each, then both scored a touchdown in the first overtime, for a 35-all score.
Cass (0-8) was led offensively by Kadeem Buford, who returned two kickoffs for touchdowns, Brandon Etheridge, who tossed three touchdown passes, and kicker Guadalupe Rangel, who hit the field goal in overtime.
The loss denied Cass's quest to break into the win column on the season.
"How much closer can you get than double-overtime?" head coach Rick Casko asked. "I feel bad for the kids because they played so hard."
He added he is proud of their play against the Grizzlies. "We played a good football team and some of our players were dinged up so we had some kids who had to step up."
The coach said the game showed continued improvement by the Colonels. "We got better. We improved but we still made some costly mistakes like jumping offsides, a high snap and an interception. But our kids never stopped playing hard."
"We tried to find every possible way imaginable to give this football game away tonight," said Creekview (3-5) coach Al Morrell. "But it's like I told the boys, we turned around at the end and fought our hearts out and found a way to win the game when it counted."
Cass got off to a great start when Buford fielded the opening kickoff at the 1-yard line, headed for the wedge and then was gone on his 99-yard touchdown run, giving the Colonels a 7-0 lead after the PAT by Rangel.
The Colonels then turned opportunistic the next series when Creekview fumbled the handoff and senior offensive lineman Dalvin Jeffries recovered it deep in Grizzly territory. The Colonels cashed it in with a 5-yard touchdown pass from Etheridge to Blake Kirk to go up 14-0.
The Grizzlies responded with a touchdown drive and pulled to within 14-7 after the PAT was made.
That score lasted only briefly as Buford fielded the Creekview kickoff around the 15 and again took the scenic route all the way downfield to put the Colonels up 21-7 and Rangel split the uprights.
The Grizzlies struck back late in the second quarter, however, and a long pass let them enter the halftime locker room down just 21-14 with a little momentum.
The Grizzlies tied the game at 21-all their first drive of the second half and they later scored their final touchdown of regulation, helping them to a 28-21 lead.
Cass tried to cut into the lead later in the half with a field goal but a high snap frustrated the attempt.
With about two and a half minutes remaining, Etheridge capped the team's best drive of the night, 51 yards in nine plays, by hitting Najae Jackson for a 20-yard touchdown to tie the game at 28 points and forcing the overtime.
Etheridge's third touchdown pass of the night came in the first overtime, when he hit Jordan Cothron for an 11-yard score.
The Grizzlies were led on the ground by D'Ondrei Hubbard, who racked up 175 yards and three touchdowns on 26 carries.
Defensively, the Colonels were led by Ronnie LaFollette, with seven solo tackles. Justin Reed had six and Mark Morton had five.
Jeffries took possession of two fumbles for Cass.
-- Chase Wallace of the Marietta Daily Journal contributed to this report.
SCORING BY QUARTERS
1 2 3 4 OT1 OT2 F
CRE 0 14 14 0 7 6 41
CAS 14 7 0 7 7 3 38
CASS SCORING SUMMARY
-- Kadeem Buford 99-yd kick return (Guadalupe Rangel kick)
-- Blake Kirk 5-yd pass from Brandon Etheridge (Rangel kick)
-- Buford 85-yd kick return (Rangel kick)
-- Najae Jackson 15-yd pass from Etheridge (Rangel kick)
-- Jordan Cothron 11-yd pass from Etheridge (Rangel kick)
-- Rangel 32-yd field goal
Cass Creekview First downs 15 30 Rushes-yds 23-31 65-389
Passing yds 204 90
Comp-Att-Int 14-30-1 6-10-0
Total yds 235 479
Penalties 11-78 14-98
Fumbles-lost 0-0 3-3
Punts-yds 4-27 3-19
Rushing -- Cass: Kelin Wells 9-16, Brandon Etheridge 13-10, Andrew Hunt 1-5.
Passing -- Cass: Etheridge 14-30-204-3-1.
Receiving -- Cass: Wells 3-73, Najae Jackson 3-72, Chaz Rokins 3-13, Blake Kirk 2-25, Andrew Hunt 2-10, Jordan Cothron 1-11.