West Ham United officially announced today the signing of Argentine striker Valentín Castellanos from Italian club Lazio on a four-and-a-half-year contract with an option to extend for an additional season, according to the club's official website.

Castellanos is distinguished by his ability to play as a deep forward, create goals, link play, and contribute to teamwork. He has had an impressive career in both the Spanish and Italian leagues.

The Argentine striker is a key target for coach Nuno Santo and will be ready to participate in the team's upcoming Premier League match against Nottingham Forest on Tuesday evening.

Although the club did not disclose the financial cost of the deal, some reports indicated that signing the player cost the English club's treasury 29 million euros.

Castellanos said: "Every match is a battle, and I will put all my energy and fighting spirit to defend this jersey and achieve the team's goals day by day," affirming his full commitment to West Ham and the team's fans.