Cristian Romero had to come off early in their 4-3 loss to Chelsea, while Brennan Johnson was also taken off.
Micky van de Ven was another who was unable to play the full 90 after returning to the starting lineup.
Post-game, the Australian said: “Romero is just obviously hugely disappointing. He felt something in his quad. He trained really well. He wasn't the one I was worried about, to be honest, but, you know, it's just like I said, the way the season's going for us unfortunately. So we just have to wait and see.
“Brennan just didn't feel well. He didn't feel well at half-time, but he wanted to give it a go, but he just wasn't feeling 100% so I had to take him off.
“And then, well, the plan was always for Micky to play 60/70 (minutes) today. Obviously, I thought Romero would be okay to play 90, but Micky, probably 60/70. So we were always going take him off. He didn't feel anything significant. He just felt tightness, but we were always going to take him off anyway.”
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