Ollie has admitted that winger Martin Rowlands' absence in the R's midfield is a big blow, not just in an attacking sense.
The Rangers boss confirmed that last season's Player of the Season's ability to track back and defend will be sorely missed.
"When Rowlands is on the right, he plays like an attacker, but he defends so well, too," he said. "Lee Cook, on the left, is an out-and-out winger who is very entertaining.
"But when he was at Watford, they sometimes didn't play him away from home, because they know what he can be like at times.
"I had to start with two genuine wingers - Cook and Jamie Cureton - against West Ham, and ideally I wouldn't have gone to Upton Park and been that wide open."
Rowlands has been diagnosed with a broken bone in his right foot leaving the Irish international on the sidelines for six weeks.