The Frenchman has spent the past three years working to fine-tune his high intensity, high pressing, style of play.
It’s a philosophy that relies on players who are energetic and hard working.
And Ismael revealed players have to be able to hit certain numbers before he will consider signing them.
“The principle is intensity – the players in each position must hit certain numbers,” the boss said when asked how he identifies players.
“I have gathered over the last three years all the information and numbers from the all teams I played with in our formation. And I can say exactly which number they need to reach.
“The first choice before I pick a player is to see whether he can reach those numbers.
“If he can, we go to the next step, the quality of the player and the mentality of the player.
“Then at the end of the day we make a decision over the player.
“If a player isn’t reaching the numbers, it’s a question of can he? If not, you move onto the next one.”
Ismael believes having such a clear transfer strategy was particularly beneficial this summer – with the boss only arriving at The Hawthorns in June.
“It’s helped us we improved a lot straightaway with West Brom,” he added. “We didn’t waste our time in the market. A lot of players came on the table, but you don’t need to assess all the time because we knew exactly what we wanted.
“This is the right way and at the end, we make the decision – it’s not as though the player is forcing us from the outside, we know exactly what we want.
“Now it takes time to have all the players hitting the numbers we want in each position.
“But we are really satisfied with our squad at the moment.”