Sentence:  After four grueling laps, the race had come down to a sprint. Into the <WSD>straight</WSD>, although my legs were burning, I called on them for more, and they responded. On my inside the maroon singlet came with me, until it was just the two of us heading for the line. 
Meaning of the word marked with <WSD> tags:  Something that is not crooked or bent such as a part of a road or track.