But after Adam Johnson, Steven Fletcher, Carlos Cuellar, Louis Saha and Danny Rose arrived on Wearside in recent weeks, O'Neill will send out some of his younger players to gain some first-team experience, with Connor Wickham and Ji Dong-Won among those expected to benefit.
"When the transfer window was still open, the most important aspect for me was what players we had available and to make sure that we were covered," O'Neill told the Shields Gazette. "But now the emergency loan window is getting ready to open this weekend, I'll look at other things.
There is the possibility that maybe some players will go out on loan. "The key thing there is that they would be going on emergency loans, which means they could be called back after 28 days if necessary. "I don't mind allowing players to leave on emergency loans because they will be getting games and - providing we can survive the first 28 days - if we pick up injury problems, we can recall them."