The Baggies take on the Cherries in their first competitive match of Ismael’s tenure on Friday.
But as well as goalkeeper Sam Johnstone, they’ll be missing a handful of other players.
Reach, who signed on a free transfer on Monday, is currently working on his fitness as he bids to part of Ismael’s high intensity side.
“He (Reach) is able to play, but he’s not ready to play because I think he is about three weeks behind the other players,” the boss said. “For sure, he trained in the off-season but he didn’t train with the players so it’s not the same.
“Especially with us, with our intensity, the season will be very long and he will play, but at the minute it’s about making sure he can implement the principles.
“We can work with him properly to make sure in the next 10 days he can have a better fitness level than now.”
Midfielder Castro, meanwhile, will be granted a little extra time after dislocating his shoulder last week.
It was believed that the summer signing might be ready for Bournemouth, but he’s still on the road to recovery and won’t be risked
Fellow youngster Gardner-Hickman has a slight knee injury.
“We only have two injuries, young players, with Quevin Castro who disclocated his shoulder, and Taylor got a kick on his knee, so it’s nothing with muscles,” Ismael explained.
Matt Phillips and Alex Palmer didn’t feature in the friendly against Blues last weekend.
Phillips, who has been playing as a centre forward in pre-season, was in close contact with someone who was displaying Covid symptoms so was forced to isolate.
Goalkeeper Palmer, meanwhile, was in attendance at St Andrew’s, but he was unable to be named in the squad after suffering concussion in training.
But both players are now back in training.
“It’s a good sign, we need to keep the players together,” Ismaeil added.
“Matt Phillips trained this morning (Tuesday), Alex Palmer trained this morning, so everyone is on board now for the first game.
“We had a great training session today, onto the next one.”