A lack of conviction in front of goal has been a real problem for Carlisle United in recent months.
However, a return to form for talisman striker Lee Miller and a first career goal for Brad Potts helped brush that to one side as the Cumbrians ended a miserable January with a much-needed win thanks to a powerful first-half display.
Misfiring MK Dons continue to struggle to keep pace with their play-off rivals and they looked out of sorts and out of ideas as they left Brunton Park with another away defeat o contemplate.
Both sides created chances in a game which simmered slowly to the boil - and the Dons were first to ask a question when Reeves sent Long into the box.
He went for a shot from a very tight angle and Fleming spread himself to beat it away.
Set pieces were a threat for the Cumbrians and former Dons defender Sean O’Hanlon tested Martin with a powerful header as he made a Berrett corner his own.
The stopper adjusted and plucked the ball from beneath his bar.
The hosts upped the pace as half-time approached and a fierce free-kick from wide on the right brought a first goal in nine games for talisman striker Lee Miller when he got the slightest of touches to finish off a wonderfully struck Tom Lawrence effort.
The lead was doubled just before the break when Berrett surged forward through midfield.
David Amoo matched him stride for stride and his low cross across the face of goal left the ball on a plate for Brad Potts to score the first goal of his career.
Lawrence then wound his way to the byline to earn a corner and the prolific Amoo made it 11 for the season with an unstoppable header from the resulting corner.
CARLISLE: Fleming, Chimbonda, O’Hanlon, Meppen-Walter, Robson, Potts, Noble, Berrett, Amoo (Dempsey 85), Miller (Drennan 76), Lawrence (Symington 90). Subs - Bouzanis, Livesey, Buaben, Guy.
Goals: Miller (39), Potts (42), Amoo (58).
MK DONS: Martin, lewington, Flanagan, Hodson, Gleeson, Potter, Reeves, Alli (Powell 46), Long (Bowditch 60), Carruthers (Baldock 46), Kay. Subs - Chadwick, Smith, McLeod, McLoughlin.