Sale Sharks director of rugby Bryan Redpath has described his side's performance as being "not good enough" following Friday's defeat to London Welsh.
Despite a late fightback at the Salford City Stadium, the hosts suffered their fourth consecutive defeat of the new season.
"You can't hide behind that performance tonight because, as a group, it wasn't good enough," said Redpath.
"It let a lot of people down that came along tonight. We need to find out why, but there's not many answers coming out at the moment.
"I apologise to every Sale supporter. They pay good money to watch and I will be doing my utmost to rectify that."
The loss has left the Sharks 11th in the Aviva Premiership table.