West Bromwich Albion manager Tony Mowbray believes his side are facing a "tough period" after losing 3-1 to Derby County.
Goals from Ebou Adams, Jerry Yates and Nathaniel Mendez-Laing, the Baggies' sole score coming from striker Adam Armstrong, subjected the Midlands club to their fifth loss in six games.
"Obviously, it's a tough period for us," said a dejected Mowbray to BBC Radio WM.
"I haven't seen anything since I've been here like the goals we conceded today from the set-plays.
"It's so unlike us. Two set-play goals from a hard-working, honest team.