I think the ref was right at that moment in time. He used his experience and judged that Earl was still fighting back although taking heavy shots. Confirmed by a decent shot coming back from Earl, rocking Katsidis. Although it was ruled a knockdown I'm not sure his gloves touched down. Katsidis looked a bit shakey immediately after that and the count probably helped him clear his head.

Great fight, hope to see a bit more of Katsidis now.