The Italy international had been linked with a move to the Turin giants all summer and agreement was finally reached just hours before the end of the European transfer window after the Italian outfit increased their bid.

Lyon will receive a further million euros in performance-related add-ons under the terms of the deal.

A statement on Lyon's official website read: "The transfer of Italian international defender has been realised.

"[Juventus] agreed to increase their offer to over 2million euros plus 1million euros based on future athletic performance."

Grosso, now 31, joined Lyon from Inter Milan in the summer of 2007, and was under contract with the French side for a further two seasons.

He scored the winning penalty for Italy in the 2006 World Cup final and the following year moved to Lyon, where he scored twice in 52 matches and won the 2008 Ligue 1 title.

Grosso's arrival at Juve has been delayed due to international commitments.

He will join with Italy's squad for Saturday's World Cup qualifier against Georgia in Tbilisi before returning to Italy for the Azzurri's match with Bulgaria in Turin the following Wednesday.

Lyon have also confirmed the departure of Anthony Mounier to fellow French outfit Nice for a fee of 2.5million euros.

Juventus later confirmed Grosso has signed a three-year contract with the club.

"The acquisition of Fabio Grosso gives our team, which is already very competitive, further quality," said Juve club administrator Jean-Claude Blanc.

"The international experience and the characteristics of a world champion will be useful for a side that has to compete in three fronts.

"With this last transfer our busy transfer market comes to an end."