Brentford forward Josh Dasilva scored twice as Brentford thrashed Sheffield Wednesday 5-0
Sheffield Wednesday midfielder Barry Bannan admitted they were "terrible" in Saturday's 5-0 defeat at Brentford.
The Owls were third in the Championship at Christmas but have won just twice since and are now only nine points clear of the relegation zone.
Wednesday were charged with misconduct by the EFL in February and could face a points deduction.
"We've let the club down, the fans down and the badge down," Bannan told BBC Radio Sheffield.
"The players need to start taking the blame because the manager works hard day in and day out.
"It's 11 v 11 and it's not good enough. You can't go from playing as well as we did against a strong Manchester City (in the FA Cup) in midweek and losing 5-0. It's unacceptable.
"Not one of us in that changing room will be able to go home tonight and look at ourselves in the mirror. We've not shown up today."
- Brentford hit five to move up to fourth
Boss Garry Monk, who was appointed in September, has dropped a number of senior players including goalkeeper Keiren Westwood, midfielder Sam Hutchinson and striker Jordan Rhodes.
Scotland international Bannan denied, though, that a lack of team spirit or concern about a possible points deduction was behind the team's dismal form.
"I think the gaffer has been more than fair with people. He has given everyone a chance, whether they have taken it or not is a different thing," he added.
"Everyone gets on well. Maybe we are too nice to each other. At the top teams you need to be able to dig each other out.
"We were talking about the impact of losing points when we were third so we can't turn around now and say that everything that's going on in the background is affecting us. Our job is to go out and win and we're not doing it at the moment."
Wednesday host play-off hopefuls Nottingham Forest next Saturday.
Source: bbc.com