The scoreless draw prevented Kansas City from clinching a playoff spot, but it can still do so this weekend if either New England or Philadelphia suffers a loss.
Houston dominated play throughout the first half, but was foiled by Nielsen. It was his 13th shutout of the season, which has two games remaining.
Kansas City remained in second place in the Eastern Conference, one point behind front-running New York. Houston is in third place, four points behind Kansas City.
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