Hennessey's error led to Crystal Palace losing 1-0 against Aston Villa at Villa Park.
It was a night to forget for Crystal Palace at Villa Park as they were only the second side to lose to Aston Villa in the Premier League this season.
A Joleon Lescott goal was enough to give the bottom of the table side all three points, but the focus is on a terrible error from Eagles goalkeeper Wayne Hennessey as he failed to keep out the header from the Villa defender.
If the reaction on Twitter is anything to go by, a lot of the Palace fans are willing to cut Hennessey some slack for his error, and have pointed out that he has been in pretty good form for the club for much of the season as Palace have enjoyed a terrific start to the season.
The defeat, however, means it is four league games without a win for Alan Pardew's men, who have dropped to seventh in the table - though one gets the feeling that the club's fans would have taken the position at this stage of the season if it had been offered in August.
As it stands they are five points off the Champions League places, and a place in Europe next season remains a firm possibility.
Here is a selection of what Palace fans had to say on twitter about their goalkeeper after his blunder:
Hennesey will get the blame if we lose this but the fact is, several players have been shocking #cpfc— Andy Lee (@angryleeuk) January 12, 2016
Knew #cpfc would struggle tonight. We need a striker massively. Can't have a go at Hennesey he has been class for us of late— Ross Mitchell (@rossmitch1204) January 12, 2016