He is particularly worried about the midfield area, with John Moncur struggling to overcome a knee injury.
"You only have to look at our midfield with John Moncur and Steve Lomas injured - it leaves us very very bare in that area.
"John is improving but the game against Arsenal at the weekend might be a bit too soon for him and there's no doubt the squad is thin.
"We have Laurent on the left hand side as cover and the young boys like Richard Garcia and Grant McCann as the next in line."
But there are no quick fixes in the transfer market, and Paul admits: "There are lots of different things being discussed but certainly not anything definite."
But one area where there is a selection problem for all the right reasons is up front, where Fredi Kanoute should return - possibly at the expense of Old Trafford goal hero Jermain Defoe.
"Jermain has really grabbed hold of his chance and improved week in, week out," says Paul.
"The greatest compliment you can pay him is that you always feel he might score a goal, and to be saying that about a 19-year-old in the Premiership is quite a statement.
"Fredi will be raring to go by the weekend I hope, as he has been going full tilt in training, and I'm sure he will be putting his name in the hat for the Arsenal game."
Paul reckons the game will be a good test to see whether Saturday's win at Manchester United - who have since thrashed Derby 5-0 - was a one off or part of a sustained revival.
"Arsenal are the best team in the country on form at the moment, with a fantastic away record as well, and quality players everywhere," says Paul.
"They have pace and athleticism and you know that you have got to be on top of your game to even give them a good game. That is something our lads are fully aware of and they are looking forward to it."