The Ovenbird is most often seen as it walks along the forest floor. It might be confused with a sparrow but the bill is too narrow and the upperparts lack streaking and spotting. Other ground-dwelling warblers with streaked underparts are the waterthrushes but they constantly wag their tails and have white or yellow superciliums and lack eye rings.
Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.