The Reds are flying towards the top end of the Championship and have had a settled starting line-up and squad in recent times and have fully exploited the five-substitute rule in force in the second tier which was introduced in mid-November.
It has enabled Ismael to rotate his forward players, in particular, but despite being named on their nine-strong matchday squads, several players are struggling to get game time.
Clarke Oduor has been an unused substitute in the Reds' last 19 matches in all competitions and his last appearance came just before Christmas at Swansea.
Keeper Jack Walton has not featured since the game at Watford on January 19, while Herbie Kane has not started a league game since the end of January.
Kane's telling contribution from the bench in the weekend win at Bournemouth was proof of the importance of the Reds' squad, with patience being a virtue to the Reds' squad, with Collins providing conclusive proof of that, according to Ismael.
He said: “He (Kane) has had a lot of games this season. A lot of guys have played and even young guys like Jasper Moon have had a chance and all the players who have to stay focused and involved because you don’t know what will happen for sure.
“At the moment, everyone is ready and fit and it is a good feeling, but you never know. Things go quickly and you can need everybody (else) in one minute and we have to be there.
“It is the same with the substitute players. When they come in, they know exactly that they are needed and we will stay focused to change games and have an impact on the game.
“It is exactly the same for the other guys who don’t play. Brad Collins was the same as for months as did not play and he was unhappy and suffered about the situation.
"But we spoke with him and said: ‘stay, keep going and you never know what happens’ and now the situation changes.
“But it will be the same situation for Jack and Clarke Odour. We will need all the players. I cannot say when but we will need all the players."