Not according to the etymology. https://www.etymonline.com/word/nigger

1786, earlier neger (1568, Scottish and northern England dialect), negar, negur, from French nègre, from Spanish negro (see Negro).

All of these languages are latin-based languages... So there must be a latin root. If you dig further you find

from Latin nigrum (nominative niger) "black, dark, sable, dusky" (applied to the night sky, a storm, the complexion), figuratively "gloomy, unlucky, bad, wicked,"

So yes negro exists in the middle but not as the source necessarily... It would have evolved (if I read the etymology correctly) as Nigrum -> Niger -> Negro/neger/negar/negur -> Nigger.