Andy Robertson's shoulder injury has left Kostas Tsimikas playing week-in, week-out for Liverpool. It's not the first time that the Greek has done this, of course, but his performances have come under the microscope.
Away at Toulouse, for instance, Tsimikas struggled badly and was hooked at half-time after giving away a goal. However, he rebounded remarkably well against Brentford - he was integral for both goals in a 2-0 win.
Jurgen Klopp was asked for his thoughts on Tsimikas after that turnaround in form. The Liverpool boss says he's 'really happy' with what he's seeing now from his no.2 left-back.
"Kostas needed rhythm as well, it's like he was flying when he came into the team - but he knows that," he told a press conference on Wednesday. "It's very important for a player who was waiting that long for a run of games.
"But he improved now. The last two games were very good. [Against Brentford] you could see how big the change was after he setup the goal. He was involved for Diogo's goal as well.
"He was much more stable and we all know that if he's stable then he can produce some beautiful things. Especially crosses, set-pieces, and all these things. We need that, so we're really, really happy."
This is ultimately why you need squad depth at the top level. Robertson is out for a while now and having Tsimikas capable of performing like this is a massive advantage - the Reds aren't feeling the Scot's absence too much.
But it's also a demonstration of why you need patience. When players aren't out there every week, it will take them time to adjust to the change of first-team football.
Tsimikas may have started slowly but he's been delivering now and showing exactly why he has his place in Liverpool's squad.