MILAN (AP) -- German Denis scored a hat trick as struggling Atalanta stunned nine-man Roma 4-1 in the Serie A on Sunday.
Guido Marilungo put Atalanta ahead in the 10th minute before Denis scored his first goal in the 19th.
Roma gave itself hope when Fabio Borini pulled one back shortly afterwards.
However, Denis struck again two minutes after the interval and Pablo Osvaldo was dismissed for an off-the-ball incident. Denis grabbed his third in the 66th as the Argentine took his season tally to 15.
Roma had another man sent off eight minutes from time when Marco Cassetti saw red for dissent.
Roma remains fifth, ahead of the rest of the weekend's fixtures, while Atalanta is still seven points off the relegation zone after Lecce beat 10-man Cagliari 2-1. Siena also won, routing Palermo 4-1.