Juventus threw down the gauntlet to their Serie A title rivals Napoli by pulling four points clear at the top with a convincing 2-0 victory over Internazionale.

February has seen the reigning champions catch up to and then finally overhaul free-scoring Napoli, but they were only one point clear of the southerners heading into the 27th round of games.

It took second-half goals from Leonardo Bonucci and substitute Alvaro Morata – the latter scoring a late penalty – for Juve to earn a breather, safe in the knowledge their status as Scudetto favourites cannot be touched by Napoli when the Azzurri visit Fiorentina on Monday.

Roberto Mancini’s Inter, the former table-toppers who were distinctly ineffective in Turin, only deigning to threaten their hosts at the death, now face the unenviable task of attempting to overhaul Juve’s 3-0 lead in the Coppa Italia semi-finals when the Italian giants meet again on Wednesday.

The results of Sunday’s earlier games transformed the make-up of the relegation battle, with Sampdoria, Palermo and Carpi making gains while Genoa, Frosinone and Hellas Verona sank further into the mire.

Vincenzo Montella’s Samp were previously without a win in eight attempts but snapped that bad run to pull five points clear of the bottom three after goals from Fernando and Fabio Quagliarella settled a 2-0 home victory over Frosinone.

The promoted southerners are four points behind Palermo, who ground out a point from a goalless draw with Bologna in Sicily, thanks largely to the heroics of stand-in goalkeeper Josip Posavec.

Simone Verdi’s second-half penalty earned 19th-placed Carpi a valuable point from a 1-1 draw with Atalanta. The mid-table Bergamo side took the lead through Jasmin Kurtic but a first victory in 12 attempts eluded them as Verdi levelled from the spot with 15 minutes remaining.

Basement boys Hellas look increasingly doomed. After winning twice in February to recover a lost sensation of hope, a 2-0 defeat at Udinese means they are now nine daunting points behind Palermo.

Emmanuel Agyemang-Badu and Cyril Théréau scored the goals for a team who, sitting in 14th place, are still not totally assured of top-flight football.

Also facing a late scrap to ensure they avoid the drop are Genoa, with Gian Piero Gasperini’s men submitting to upwardly mobile Chievo after Lucas Castro’s diving header clinched a 1-0 win for the Flying Donkeys.