Cheltenham manager Mark Yates left his players in no doubt how angry he was after the 4-0 defeat at Southend.
The Robins were reduced to 10 men after just 19 minutes when Sido Jombati saw red for fouling Michael Timlin, and Southend were comfortable winners thanks to goals from Kane Ferdinand, Ryan Hall, Freddy Eastwood and Bilel Mohsni.
Yates said: "Sido's challenge was rash and he knows it has cost us but I have seen teams win with 10 men.
"Southend played well but we gifted them the first goal and then [goalkeeper] Jack Butland has not had the best night for us.
"But we are seventh and we must make sure we stay in a play-off position. We can definitely do it but we have got to be much better than we were for 75 minutes.
"We are very disappointed but Southend could have scored more and so we have to go back to the drawing board. The players know how angry I am."