A brace from Luis Alberto helped Lazio secure bragging rights over Roma in the Derby della Capitale on Friday.
The Spaniard made it five goals in six appearances with an effort in each half to inspire a 3-0 win over their rivals.
Ciro Immobile opened the scoring for Simone Inzaghi's side after quarter of an hour and they clinched a crucial second via Alberto nine minutes later.
Any nerves were put to bed when Lazio grabbed a third midway through the second half at Stadio Olimpico and the result moves them up to sixth while Roma remain in third place.
Bayer Leverkusen's Bundesliga title hopes were dealt a further blow after they conceded late at Union Berlin to lose 1-0 on the road.
Substitute Cedric Teuchert came off the bench to score an 88th-minute winner for Union Berlin, who are now fourth in the table after a seventh win of the campaign.
Leverkusen had started the season in spectacular form, but have lost three of their last four league games.
Monaco survived a late onslaught to triumph 3-2 at Montpellier following Wissam Ben Yedder's double.
Kevin Volland fired the visitors ahead before France international Ben Yedder scored either side of half-time.
Montpellier staged an admirable fightback with Sepe Elye Wahi and Andy Delort on target, but Niko Kovac saw his team hold on for a third straight victory in Ligue 1.