Klopp named a fairly conservative team for the second leg tie at Anfield, with Milner starting alongside Wijnaldum and Fabinho in the middle of the park.
After the hour mark, with Liverpool chasing the game knowing two goals would take them through to the last four, Klopp changed things up and brought on Thiago Alcantara for Milner.
In doing so, he instructed Milner to hand over the captain’s armband to Wijnaldum, who is in the middle of a contractual stand-off with the club.
The Dutch midfielder is set to leave at the end of the season at the end of his contract, having failed to sign an extension.
And former Anfield hero Jose Enrique believes Klopp should have given Andy Robertson the honour of captaining the side when Milner was brought off.
Robertson has been one of Liverpool’s most reliable players in recent years, and Enrique believes he should be in contention to be one of the reserve captains within the squad.
“I believe Klopp has given Wijnaldum the armband as an appreciation for what he’s done before,” he said to Empire of the Kop.
Every Monday we deliver our verdict on the weekend’s fights and, more importantly, what’s next for the winners and losers.
Signing up is easy, just click this link, enter your email address and select ‘Boxing’ from the list.
“He is not signing a contract so, for me, he would not be my captain when Virgil van Dijk, Hendo [Jordan Henderson] and Milner are not on the field. I would give it to Trent [Alexander-Arnold] or Robbo, but I’d probably go for Robbo.
“I believe the way he plays and the way he always gives 100% makes him truly deserving of it. He is a top character.
“Gini is a legend of the club for what he’s done, but he’s leaving – I wouldn’t give the captaincy to someone who’s leaving.
“Obviously I respect Klopp’s decision, and there’s no question about Gini’s performance last night – he was great! He’s one of the best midfielders in the world, still – and I don’t mind him thinking of his future.
“All players do the same, as he has one big contract left now he’s in his thirties.
“Thankfully we have Curtis Jones, who has the ability to grow into the team when Gini leaves.”