The Longford hurlers were too strong for Cavan winning 2-14 to 0-9 at Kingspan Breffni in Allianz hurling league division 3B.
Adrian Moran’s men led 1-7 to 0-4 at the break and had six different scorers in the opening half; Emmet Corrigan with the game’s opening goal on five minutes.
Cavan’s chances of overturning the deficit were dealt a blow just before the interval as Philip McCabe was shown a straight red card on the stroke of half-time.
Fiachra Hughes reduced the margin to three points on 50 minutes before Cathal Mullane restored Longford’s five-point cushion seven minutes later.
Cavan were down to 13 men on the hour mark as Anthony Sheridan was sent off and Johnny Casey scored Longford’s second goal with nine minutes remaining.
The visitors ran out comfortable winners and are already guaranteed at least a semi-final place with one group game remaining between Fermanagh and Leitrim.