The two sides go head to head in the Tyne-Wear derby on Sunday but O'Neill believes that the Magpies and manager Alan Pardew deserve credit after qualifying for the Europa League last season.
"This time last year, I wasn't working, so I was looking at it from afar, and perhaps when the results were coming in each weekend and Newcastle were still going strongly, I maybe felt, like a lot of people, they would do well to keep it going," BBC Sport quotes O'Neill as saying.
"But they did, they kept it going. They deserved all the accolades going, there's no question about that. That's not to defuse any situation, that's just how I view it. It was terrific. Alan Pardew won the Manager of the Year and deserved that, so it was a terrific effort."