Udinese's Cyril Thereau (C) celebrates after scoring a second goal against Inter Milan during their Italian Serie A soccer match at the San Siro stadium in Milan December 7, 2014. [Photo/Agencies]

MILAN - Roberto Mancini was still waiting for his first Serie A win since returning to Inter Milan after they slumped to a shock 2-1 home defeat by Udinese at San Siro?on Sunday.

When Inter won the Scudetto in the 2006-07 season under Mancini, they lost only one league game all season, but they have lost two out of three since he returned for a second stint at the club to replace Walter Mazzarri.

Inter dominated the opening half of play against Udinese, whose coach Andrea Stramaccioni was facing his former club for the first time, but had only a Mauro Icardi goal to show for it.

Bruno Fernandes levelled with a superb strike from just outside the box in the 60th minute and Cyril Thereau scored the winner 11 minutes later.

The French forward took advantage of a mis-judged backward pass by Rodrigo Palacio, rounded Samir Handanovic and easily scored into the empty net.

"I'm not sure what happened in between halves," Mancini, whose side are languishing in 12th place with 17 points, told Sky Sports Italia.

"I haven't had enough time to reflect on it. After Udinese tied the score we stopped being a team. I'm extremely disappointed."

Genoa coach Gian Piero Gasperini said he could hardly believe the Serie A table after Luca Antonelli's first-half header gave his side their seventh win in 14 Serie A games this season.

"When I look at the table, I'm in disbelief," Gasperini told Sky Sport Italia. "However, we've earned and deserve every point."

Genoa, who have 26 points, won the last of their eight Italian titles in 1924 and finished 14th last term having narrowly avoided relegation in the two seasons before that.

Napoli dropped two points behind Genoa in fourth, with Empoli taking a 2-0 lead with goals from Simone Verdi and Daniele Rugani.

Napoli replied with two goals in five minutes as Duvan Zapata headed in from a corner and Jonathan De Guzman scored with a low shot after Christian Maggio's centre was deflected into his path.

Lazio sent table-propping Parma to their fourth straight loss, and their 12th in 14 games, as they won 2-1 at the Tardini stadium.

Atalanta, who had only mustered five goals in their first 13 matches, scored three in eight minutes either side of halftime as they came from behind to beat Cesena 3-2.