Darren Moore says his side need to learn fast after going down 1-0 at Wigan Athletic.
In a scrappy game with few chances, Albion were left to pay when Josh Windass found space on the edge of the area to drill past Sam Johnstone in the 74th minute.
Albion's day then got worse when Jake Livermore was shown a second yellow card late on as the Baggies pushed for an equaliser.
Moore said: “It was a difficult game today, Wigan made it very hard for us.
“They competed for every ball and hustled us when we had possession.
“These are the hurdles that you are going to come up against in the Championship and our players need to learn very quickly.
“It was a tight game and there wasn’t much in it. The vital chance fell to them and the boy put it away well.
“It was then an uphill task trying to break the ten men down.
“I take nothing away from Wigan. They came out with an excellent game-plan and they worked hard for their victory.
“We will analyse and move on quickly for Wednesday.
“The way this division presents itself, if you’re winning games then you get another game quickly to keep the momentum going and if you’ve lost, you get a chance to turn it around quickly.”