It was a loss of down penalty and Havre de Grace capitalized off the turnover on downs.
The Warriors drove 92 yards in 10 plays, culminating with a 33-yard touchdown pass from Flosser to Jordan Day.
The Warriors passing game struck again on the next possession.
Flosser (13-for-18, 216 yards) connected with Christian Penrow for the 40-yard score. Penrow caught the pass about 15 yards down the field and then with a few nice moves, covered the remaining 25 yards into the end zone.
"I actually came off an audible, changing my route from a seam to a post," Penrow said. "After I caught the ball in the open field, the defense just started collapsing in different ways, so I just worked my way into the open field to the end zone."
Just 14 seconds later, the Warriors were back in the end zone for a 28-0 lead.
The Hawks fumbled the ensuing kickoff and Jordan White made the recovery inside the Hawks five yard line.
Stansbury took it in from there and Clay Harris, who was a perfect six-for-six in point-after-kicks, supplied the extra point.
North Harford finally got on the scoreboard, but not without a little confusion.
The clock, which was said to be official, showed no time left in the half. The referee, though, said two seconds were left.
"The team was down, because [North Harford] came out playing stronger in the second half and coach called one of my favorite plays and I broke up the sideline, caught the ball and I just made a play for us to keep on top," Penrow said.
Penrow beat the Hawks defense down the near sideline, grabbed the pass and raced untouched to the end zone for the 58-yard score. Penrow finished with three catches for 98 yards.
The game's final points were scored midway through the final quarter.
RaShon Bray's fumble recovery gave the Warriors possession at the North Harford 13.
The Warriors overcame a personal foul on first down with a Flosser to Will Ashman pass that covered 26 yards to the Hawks two.
The winning score came with 1:50 left to play with Cougars quarterback Brady McMaines hitting Justin Williams for a 75-yard game-winning touchdown. McMaines passed for another score and ran for one as well to lead the Cougars scoring.