With a couple of changes to the line-up expected, Bilic has warned his pupils every performance will be closely scrutinised.
Now the deadline day signings are getting up to scratch, competition for places is fierce, particularly at the top end of the pitch.
Grady Diangana, Charlie Austin and Matheus Pereira are all pushing for starts after impressing off the bench at Luton, but there are options elsewhere too.
Battles are also quietly brewing in both full-back spots.
Bilic was disappointed with the way left-back Kieran Gibbs failed to close down Martin Cranie’s cross on Saturday, which could potentially open the door for Conor Townsend.
On the other flank, Darnell Furlong is yet to play a league game since his £1.5million move from QPR thanks to the fine form of youngster Nathan Ferguson.
Bilic isn’t planning on wholesale changes tonight – but will make a few – and those given a chance to impress need to take it.
“I said to the players that in training, not to mention games, you are getting pluses and minuses, like kids in school,” revealed the Croatian.
“If there are more pluses, your chances of starting or being involved in the squad for the next game improve.
“If not, you go a bit down and that’s the way it is. They call it competition, and I agree with that.”
This is Albion’s first midweek league game of the season, and the first time in the Championship Bilic will dip into his squad.
Reading only just stayed up last season, but a summer of big spending that brought in George Puscas from Inter for £7.5million and Lucas Joao from Sheffield Wednesday for £5m has shifted expectations.
Beating relegated Cardiff City 3-0 on Sunday only exaggerated those hopes.
“They had an excellent game on Sunday and changed the system a bit,” said Bilic. “They have everything based on that game.
“They were really powerful up front with two strikers, they were solid at the back with three or five, they have midfield that has attitude, power, legs, quality and creativity and they have on the wings two guys who are up and down.
“They really impressed me. They surprised me to be fair, if anything can surprise you in this league.
“As the commentator said, they’ve built a squad to challenge for promotion, they were a bit unlucky in the first couple of games, but they’re definitely a good team.”
Millwall managed to stifle the Baggies at The Hawthorns by handing them possession and sitting back.
Reading play with wing-backs, and could do the same with a back five, but they were adventurous against Cardiff.
Albion, however, boast more firepower up front now Diangana and Austin are fit and available.
But the Royals will not be the same pushovers as last season, when they were beaten 4-1 at The Hawthorns thanks to a second-half rout.
Bilic will be hoping he's handing out more A*s than Fs come 10pm.
Subs: Bond, Gibbs, Ferguson, Harper, Edwards, Pereira, Zohore.
The key battle – George Puscas v Semi Ajayi
The Romanian striker bought from Inter Milan for a club-record fee may share a moniker with one of the most famous men in the history of football, but he’s already beginning to make a name for himself in the Championship.
Two eye-catching goals in Sunday’s 3-0 win over Cardiff suggest the 23-year-old will be a force in this season. Ajayi has started the season strongly alongside Kyle Bartley, but he was prone to the odd error at Rotherham.
A battering ram of a striker, Puscas will be sure to put his abilities to the test tonight. Ajayi is in for a battle.
Memory lane – October 17, 2009
Jerome Thomas bagged a brace in a crucial 3-1 win over Reading at The Hawthorns, after the Royals had taken an early lead in the sixth-minute from Matt Mills.
Youssouf Mulumbu wrapped up the points with a fine goal three minutes from time, and it was an important victory.
After starting the season under Roberto Di Matteo on an eight-match unbeaten run, this was Albion’s only win in the next six games. But a 12-game unbeaten run at the end of the season ensured promotion was secured.