Bruce admits they've since been caught short up front due to an injury crisis.
"We were very unfortunate and incredibly unlucky," said Bruce. "When we knew in January that we were losing Benty, we had a target in mind but the numbers involved didn't work for us.
"I thought we weren't going to get value for money out of the deal so we pulled out.
"We took a calculated gamble, on the basis that Fraizer Campbell was due to return from his knee ligament damage in February.
"Unfortunately it backfired, because Fraizer never returned and now both Danny Welbeck and Asamoah Gyan are injured.
"I hope it is just a one-off, but we can't take that chance.
"We'll have to look at things in the summer because we can't allow ourselves to be left short like that again."