Liverpool's summer spending began in earnest yesterday when they sealed the £2m transfer of Argentinian defender Gabriel Paletta from Atletico Banfield.

Paletta, who celebrates his 20th birthday today, agreed personal terms and underwent a medical on Merseyside before watching his new club for the first time in last night's Premiership game with Arsenal. He will return to Buenos Aires today where he will continue to play for Banfield until the end of the season, prior to commencing pre-season training with Liverpool in July.

Though Paletta is relatively unknown outside Argentina, his signing represents something of a coup for Benitez, who was alerted to the combative central defender during his country's victory at the Under-20s World Championship last year, and who saw off strong competition from River Plate to secure the player on a four-year contract.

The Liverpool manager's desire to improve competition in his defence has been an open secret since he arrived from Valencia in 2004, when Stephane Henchoz was quickly despatched on a free transfer to Celtic to leave Jamie Carragher and Sami Hyypia as the only experienced centre-halves at the club. Having waited 18 frustrating months to strengthen that position, Benitez has now captured two central defenders in the past five weeks, Paletta and the £5.8m Danish international Daniel Agger from Brondby. He also landed Dutch right-back Jan Kromkamp in a swap deal with Villarreal for the ineffective Josemi during the January transfer window.

Whereas the 21-year-old Agger has been told he needs to improve his physical condition to withstand the rigours of the Premiership, Benitez believes the more robust Paletta will be in contention for a regular first-team place from the start of next season. The arrival of two such young centre-halves, however, does not augur well for 32-year-old Sami Hyypia's prospects of remaining an almost permanent fixture in the Liverpool team next season.

Paletta, who does not require a work permit as he qualifies for an Italian passport, is the second South American that Liverpool have signed in advance of next season. Benitez will finally welcome right-winger Mark Gonzalez to Anfield in the summer, having been denied a work permit for the Chilean international signed from Albacete last July on account of the country being ranked outside the top 70 in the Fifa world list. Gonzalez is currently on loan at Real Sociedad and will become eligible for a Spanish passport at the end of the campaign.

The Paletta deal is a further demonstration of the transfer policy Liverpool have adopted under Benitez, that of scouring the globe for cheaper, potential talent rather than proven and therefore more expensive purchases, as they attempt to develop a squad that can compete with Chelsea for the title. Since last summer Liverpool have signed over a dozen under-21 players from such disparate leagues as Denmark, Spain, France and Ghana, although they have also taken on young English players such as under-20 international goalkeeper David Martin, Hull winger Paul Anderson and Lincoln defender Jack Hobbs.

The strategy reflects Benitez's dissatisfaction with the level of talent coming through the club's own £5m academy but is, he believes, the solution to building a formidable squad without the resources available to Jose Mourinho. "You can plan for two or three years down the line but you need to win now," he said. "In my opinion, though, you can do both. Agger, Mohamed Sissoko, Xabi Alonso, even Steven Gerrard, are all young players who can deliver today and improve for the future."