Forest won their first league game of the season when they beat the Rams in August and since then, they have only lost once in the Championship.
Billy Davies' men will hope to extend that 19-game unbeaten run this weekend and Earnshaw, who has played for both teams, is confident they will emerge victorious.
"They will be wanting to beat us, just like everyone else in the Championship," Earnshaw told the Nottingham Evening Post. "Everyone looks up at who is above them; they look at the teams in the top two or three and they set their sights on beating them.
"And I am certain that will apply to Derby. So we will have to be at our best again. We have to be as ruthless as we were on Tuesday night."
Source: Team Talk