Who are the competitors in rivals poem?

In the poem "Rivals", the competitors are two young men who are rivals for the love of a woman named Lalage. The first man, Horace, is a poet who expresses his love for Lalage in his poems. The second man, Glycera, is a musician who expresses his love for Lalage through his music. The two men compete for Lalage's attention and affection, and the poem explores the themes of love, jealousy, and competition.