The Baggies, who sit top of the table, impressed in their first four Championship outings this season.
But they struggled to break down Peterborough and Millwall in their last two – with both of those sides managing to come up with a game plan that stopped them imposing their high pressing game.
Now they take on a Derby side who many are predicting will be relegated this season.
And Ismael says his team needs to win tonight to build on the positive momentum they gained from their first four games.
“Only if we win on Tuesday – this is now our purpose,” Ismael said when asked if Albion still have momentum.
“I will give you the answer after Tuesday’s game.
“We need to learn, to adjust what we do and avoid keeping the opponents alive in the game.
“We need to get back to that feeling of dominating our opponents.
“Against Millwall we didn’t have the right balance between our offensive game, where we create a lot of situations, and our defensive line, where we were too sloppy.
“We are clear out of possession. It’s not a secret now but this is where we have to adapt.
“We need to keep the intensity going, keep the pressure on.
“This is the way we have to play when the opponent just wants to fight.”
Meanwhile, defender Conor Townsend believes it’s important to remember Albion are still getting used to Ismael’s high intensity style of play.
“There has been a lot of talk about the style of play and how it’s changed and the lads have bought into it,” he said.
“We are still learning as we are going along.
“We have had a good start to the season, it does work how the gaffer wants us to play.
“It’s not going to work every single week, there are going to be times when we have got to work out how to beat the opponent.
“But we have got the players in the team to adapt.
“We weren’t amazing against Millwall - we have to hold our hands up.
“But it’s not doom and gloom. Now Derby is a massive game for us.”