Christian Dailly, Anton Ferdinand, Andy Melville, Malky Mackay, and Calum Davenport - all centre halves, of course - have all picked up injuries of late, but hopes are high that Malky, at least, will be able to return to action at Loftus Road this Saturday.
Tony highlights the number of players who can play right back at the club as proof that there is a good spread of talent in the back four.
"We have got three decent players for one spot there in Tomas Repka, Hayden Mullins, and Anton Ferdinand, and there is healthy competition," says Tony.
"Tomas is leading the way and I feel he is well suited to the position; he has calmed down as well - his discipline has improved and it is so far, so good for him."
As for centre halves, he adds:
"I think Calum has proved a excellent signing and it is just a shame that we couldn't have got him permanently; let's hope his injury isn't too serious, either.
"It was a good piece of business by us to get him on loan; we have taken a benefit from that.
"He is a good player, and Malky will prove a good signing because he has seen it and done it in this division - he is very competitive.
"Anton Ferdinand has got it all to prove - it is difficult being the younger brother of Rio but the fact that he is an England U21 international already and has had quite a few first team games shows he has a lot of promise."
Tony feels that, if all the centre halves get fit, Anton could benefit from a spell on loan, and explains:
"What you need in your late teens or early 20s is games under your belt."
As for the left back spot, with Chris Powell now signing on for another month from Charlton, Tony says:
"Last season we struggled because we didn't have a left back but this season we have two experienced ones there.
"We have two left footers and we have seen what problems England have with that.
"Chris can play left back or left midfield as well but at the moment it is looking like he is more of a left back.
"Training with Rufus and Chris Powell means he can learn all about the job."