On the second lap, Redding and Irwin exchanged a full and frank set of opinions on the grass after colliding.
Tommy Bridewell led away from pole position, with Brookes in second and Danny Buchan in third.
On Lap 11, the top four of Bridewell, Brookes, Buchan and Christian Iddon remained intact in a day marked by a lack of overtaking at the top.
However, Brookes eventually made his move, taking the lead and holding off Bridewell for the victory.
Race Two results
Danny Buchan took victory in Race One at Cadwell Park.
There was a crash in the formative stages of the race when Dan Linfoot slipped off, but thankfully he did not appear seriously injured.
Brookes held onto the lead from Buchan in second, but Christian Iddon started to move up the pack into fourth place.
Redding moved into seventh around a third way through the race as he closed on the leading pack, and made it into fifth on lap eight, eventually finishing in fourth after a mistake from Iddon.
A neat move from Buchan on Lap 11 allowed him to usurp Brookes for the lead and, in one of the least dramatic races of the season, was able to settle relatively unchallenged at the front to claim victory.
Race One results