Adam Lallana admitted Albion had underperformed as they went down 3-0 to Burnley at the Amex.
Goals from Wout Weghorst, Josh Brownhill and Aaron Lennon hauled Burnley off the bottom of the Premier League on a collective off day by the hosts.
And midfielder Lallana admits the players will have to do some soul-searching over the next few days.
He said, “Obviously the result was tough to take, but full credit to Burnley. They were fantastic today and we were below par. They were quicker to the ball and adapted better to the conditions.
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“When that happens you get punished. They were better than us all over the park.”
Albion struggled to create clear-cut opportunities although there was a nice moment in the second half when teenage striker Evan Ferguson made his Premier League debut.
“We will all have to look at our own performances, me included, to see where we can improve and move forward,” added Lallana.
“Individually, we weren’t good or collectively. It happens, we’re human. It was a bad day at the office and we’ll look to bounce back.
“It’s not good enough but we will look to ourselves and work this week to make sure we’re better next week.”