Marek Hamsik scored his 116th goal on Saturday to overtake Diego Maradona as Napoli's all-time record goalscorer and keep the Serie A leaders top for Christmas, as Inter Milan and AC Milan both suffered defeats.

Hamsik's strike before the break ensured a come-from-behind 3-2 win over Sampdoria to give Napoli 45 points from 18 games with second-placed Juventus on 41 ahead of their game against title rivals Roma, in fourth.

But third-placed Inter suffered their second consecutive defeat, falling 1-0 at Sassuolo, to drop five points behind the leaders, while troubled city rivals AC Milan slipped further away from the European places with a 2-0 loss at home to Atalanta, leaving the fallen giants 11th.

Slovakian international Hamsik joined Napoli in 2007 and is now captain and a stalwart of the side hoping to win their first Scudetto since the days of Argentine legend Maradona.

Maradona took just seven years to score his 115 goals between 1984 and 1991, helping the team to their only two Serie A titles in 1987 and 1990.

"I'm proud to have overtaken a myth like Maradona. My friends gave me shin-pads with 116 on them, but my first thought was that we were winning the game after going behind twice," said the 30-year-old Hamsik.

"Today winning was very important because we also gained points on Inter even if the championship is long."

Napoli were trailing twice in the first half with Gaston Ramirez firing in a free-kick after just two minutes to catch Pepe Reina off guard.

But Allan equalised after a quarter of an hour at the San Paolo stadium only for Fabio Quagliarella to convert a penalty to restore Sampdoria's lead after 27 minutes.

Quagliarella almost had a second shortly after, before Lorenzo Insigne marked his comeback from injury with a volley on 33 minutes following a Dries Mertens flicked cross.

But it was captain Hamsik who sealed the victory six minutes before the break, again off a Mertens cross, to overtake Argentina legend Maradona's long held mark.

Napoli held on in the second half despite being reduced to ten men following Mario Rui's sending off, to open up a four-point lead on Juventus before Saturday's late match.

"The important thing is that we won while suffering, as it's a victory that counts for even more, because Inter lost today as well," added Hamsik.

"It's practically a six-pointer. We used up a lot of energy to get the game back on track, but fortunately we brought home the result."

- Inter pay high price -
Despite their remarkable start to the season, Inter have taken just a single point from their last three matches, with back-to-back losses to Udinese and Sassuolo.

Diego Falcinelli headed in the only goal after 34 minutes at the Mapei Stadium, with goalkeeper Andrea Consigli saving a penalty from leading Serie A scorer Mauro Icardi.

Luciano Spalletti's side are third but just two points ahead of Roma, who have played two games less.

"We've lost two games but I've seen good things in these games, perhaps there hasn't been the most consistency and there have been some moments which weren't the smartest," said Spalletti.

"We paid a high price for certain episodes. To become a strong team and to consolidate on what we've done, we need to get through moments like this."

Lazio, also with a game in hand, are two points off Roma after easing past Crotone 4-0.

But things have gone from bad to worse for Chinese-owned Milan who lost to direct European rivals Atalanta, who are in seventh position.

Milan's training retreat after last week's shock defeat by Verona had little effect on Gennaro Gattuso's side.

Former Milan midfielder Bryan Cristante opened the scoring after a Gianluigi Donnarumma error in the first half with Josip Ilicic finishing off the second on 71 minutes.