Carlisle player-coach Graham Kavanagh could not hide his frustration after his side were dealt a couple of injury blows in the 4-3 home defeat to Charlton.
Phil Parkinson's men found themselves 3-0 ahead just after half-time after goals from Johnnie Jackson, Joe Anyinsah and Benson.
Carlisle levelled things up through Mike Grella, Craig Curran and Gary Madine - only for Paul Benson to head home in the dying seconds.
Kavanagh said: "It was difficult to swallow at the end. There were feelings of frustration and euphoria and at the end we felt extremely low.
"We picked up a couple of bad injuries to Francois Zoko and James Chester. It's a matter of walking wounded at the moment.
"We have a small squad and it's difficult for us at times. We are down to the bare bones but no excuses, we have no choice but to cope. We don't have huge finances or resources."