Dictionary / Vocabulary / 競り合う
せりあう
to struggle for; to compete with; to vie with
common word Also written 競合う
本命と対抗馬が競り合ったお陰で、ダークホースの彼が漁夫の利を得たってわけだ。
Since the favorite and his rival were running against each other a dark horse like him was able to pull out in front.