Jurgen Klopp revealed he had consistently reassured Naby Keita before the midfielder starred when given his chance for Liverpool against Bournemouth.
Keita scored and provided an assist on his first start of the Premier League season in Saturday's 3-0 win at the Vitality Stadium.
A £53million signing from RB Leipzig in 2018, Keita has had his difficulties since arriving at Anfield and Klopp said he frequently spoke to the Guinea international regarding his standing at Liverpool.
"Naby is sitting outside and thinks 'why don't I play?’ I get all that," the Liverpool manager told UK newspapers.
"So we stayed in contact, we talked and we spoke a lot about it, but in the end of course the player needs to have this evidence that the coach or the manager still believes in you.
"Naby had injuries and the team was and is in really good shape, so then do you change and, if you want to change, we are not flying – it's not like we won all our games 4-0 or 5-0 – so we [have] had to bring on a player who helps defending set-pieces."
After Alex Oxlade-Chamberlain opened the scoring at Bournemouth, Keita struck before setting up Mohamed Salah for the Premier League leaders.
As Liverpool's rotation continued for the encounter, Klopp said his squad understood the situation.
"It's not difficult for me to leave players out," he said.
"I didn't speak to Sadio [Mane] about it. I didn't speak to Divock Origi. I didn't speak to Bobby [Firmino] or Mo last week. I didn't speak to Hendo [Jordan Henderson].
"I didn't ask. I just have to make decisions and then next time everyone knows someone else will play.
"The boys are a really smart group who look at the schedule. They know how it is."
Liverpool visit Salzburg on Tuesday needing to avoid defeat to reach the Champions League last 16.