Juventus stopped Inter Milan from replacing Napoli at the top of Serie A on Sunday by beating their fierce rivals 1-0 and moving into Italy's Champions League positions.
Napoli currently lead Inter Milan by two points, but the latter have a game in hand.
Inter Milan closed to within a point of Serie A leaders Napoli on Monday after beating Fiorentina 2-1 and gaining revenge for last week's thumping in Florence.
Spanish clubs do not tend to splash their cash in the winter transfer windows and this season's was even quieter than usual.
Switzerland's Noah Okafor arrives at the Serie A leaders on loan until the end of the season, with an option to buy.
Inter Milan kept up the pressure on Serie A leaders Napoli on Sunday with a convincing 4-0 win at lowly Lecce which moved the defending champions three points from the summit
Napoli continued their Serie A title charge on Saturday by coming from behind to win a feverish contest with rivals Juventus 2-1 and go six points clear at the top of the table
Forwards Marcus Rashford and Alejandro Garnacho are both reportedly on the way out of Manchester United.
Inter Milan kept in touch with Napoli after seeing off struggling Empoli 3-1 on Sunday and going three points behind the Serie A leaders.
Romelu Lukaku fired Napoli six points clear at the top of Serie A with the decisive goal in Saturday's thrilling 3-2 win at title rivals Atalanta
Georgia winger Khvicha Kvaratskhelia on Friday completed a move to Paris Saint-Germain from Italian league leaders Napoli, the French champions announced.
Atalanta are four points behind Serie A leaders Napoli, and need a victory over them to keep their hopes alive.
Napoli extended their lead at the top of Serie A to four points on Sunday after beating lowly Verona 2-0 as champions Inter Milan moved second with a 1-0 success at Venezia.
Napoli took advantage of their Serie A title rivals competing in the Italian Super Cup by beating Fiorentina 3-0 on Saturday to move top of the pile.
Napoli conceded top spot in Serie A to red-hot Atalanta on Sunday after falling to a 1-0 home defeat to Lazio and dropping to two points from the summit.
Inter Milan moved a point behind Serie A leaders Napoli on Friday after seeing off Parma 3-1 at the San Siro ahead of a key Champions League clash at Bayer Leverkusen
Napoli were knocked out of the Italian Cup by Lazio on Thursday after Tijjani Noslin fired a hat-trick to hand the Serie A leaders a 3-1 last-16 defeat in Rome.
Atalanta take on AC Milan on Friday night with Serie A's top spot in their sights.