Inter Milan signed Argentine forward Mauro Zarate from Lazio, Juventus announced it acquired Netherlands winger Eljero Elia from Hamburger SV and Roma signed four players as the transfer market closed in Italy on Wednesday.
Inter paid ?2.7 million ($3.9 million) for Zarate on loan, and agreed to pay a further ?15 million for a permanent transfer.
Juventus paid ?9 million ($13 million) for Elia on a four-year contract.
Roma, which lost a Europa League playoff last week to Slovan Bratislava, signed Argentina midfielder Fernando Gago from Real Madrid, Bosnia-Herzegovina midfielder Miralem Pjanic from Lyon, Denmark defender Simon Kjaer from Wolfsburg, and 20-year-old forward Fabio Borini from Parma.
Gago, who was cast aside by Madrid coach Jose Mourinho, was acquired in a loan move that gives Roma the option to purchase his full rights after this season; while Roma reportedly paid Lyon ?10 million for Pjanic and Kjaer and Borini also joined on loan.
AC Milan signed Italy midfielder Antonio Nocerino from Palermo to replace injured Mathieu Flamini, who will miss five months following knee surgery, and the defending Serie A champion loaned defender Massimo Oddo to Lecce.
A players' strike postponed the scheduled start of Serie A last weekend, and negotiations were due to resume after the transfer window closed.
Inter had already completed a deal with Atletico Madrid for Uruguay striker Diego Forlan, but added Zarate to further bolster its attack after the departure of Samuel Eto'o to Russian club Anzhi Makhachkala.
Zarate scored 33 goals in all competitions for Lazio over the past three seasons but recently fell out of favor with the Roman club's manager Edy Reja, who relied on new signings Miroslav Klose and Djibril Cisse in a Europa League playoff win over Macedonia side Rabotnicki.
''My first choice was to come to Inter. ... Now I've got to show how much I'm worth,'' Zarate said, according to the ANSA news agency. ''There are a lot of Argentines at Inter, which is great.''
Inter announced that Forlan had signed a two-year contract.
''I want to play wherever the coach tells me to,'' Forlan told Inter Channel. ''With the national team I'm not a true striker because there's (Luis) Suarez and (Edinson) Cavani, so I manage as a sort of playmaker. But I like to play wherever my coach wants me to.''
Meanwhile, Lazio announced that Cisse injured his right ankle and would be evaluated over the next 24 hours.
Juventus, which has revamped its entire squad for the second consecutive season, also attempted to negotiate a loan for versatile defender Salvatore Bocchetti from Rubin Kazan, but that deal fell through.
Elia was used as a substitute during the Netherlands' run to last year's World Cup final.
Other players Juventus has signed this offseason include: Striker Mirko Vucinic; midfielders Andrea Pirlo, Arturo Vidal and Emanuele Giaccherini; and fullbacks Reto Ziegler and Stephan Lichtsteiner.
The 27-time champions from Turin failed to qualify for Europe with a seventh-place finish last season and are determined to improve this campaign.
In other moves, Napoli signed Argentine defender Ignacio Fideleff from Newell's Old Boys for a reported ?2.2 million; Genoa signed forward Andrea Caracciolo from Brescia; forward Sergio Floccari moved from Lazio to Parma; and Michael Bradley became the only American in Serie A after the United States midfielder signed with Chievo Verona.
As Serie A continues to struggle with dilapidated stadiums, fan violence and attendance problems, the most expensive transfers this offseason were all moves away from Italy.
Javier Pastore left Palermo for Paris Saint-Germain in a ?42 million move, Inter got ?27 million for Eto'o and Alexis Sanchez left Udinese for European champion Barcelona in a ?26 million transfer.
