Roma moved top of Serie A on Sunday after coming from behind to win 2-1 at Fiorentina, throwing down the gauntlet to Napoli and AC Milan.
Matias Soule and Bryan Cristante struck in the first half in Florence as Roma moved three points clear of the champions, Milan and Inter Milan, who thumped Cremonese on Saturday.
Gian Piero Gasperini's Roma are on 15 points after a third straight win in Italy's top flight, which came after going behind to a Moise Kean rocket in the 14th minute.
Kean almost added to his first goal of the season when he smashed another powerful effort off the post in the 38th minute, not long after Cristante had headed Roma into the lead.
Roberto Piccoli was also unlucky not to level with a volley which rattled the crossbar in the 74th minute, but Fiorentina remain winless on three points and one place above the relegation zone.
Napoli and Milan can join Roma at the top of the table later on Sunday, the former hosting struggling Genoa on a high from Wednesday's 2-1 win over Sporting Lisbon in the Champions League.
Milan meanwhile face the second test of their Scudetto credentials in as many weeks with Juventus, who sit four points behind Roma in fifth, lying in wait in Turin.
Massimiliano Allegri's team started the weekend in first place on goal difference after winning a thrilling match with Napoli last weekend.