Keita Balde Diao has officially joined Monaco in a deal that will net Lazio €30m plus up to €5m in performance-related bonuses.
He put pen to paper on a contract to June 2022 and will wear shirt Number 14.
"I am very pleased to join AS Monaco, a club with a great history. I am very happy to be here and I look forward to starting to play,” he told the official club website.
“Many players and friends spoke to me about the club, the spirit of the group and the team. When you are offered the opportunity to come here, you accept right away.
“This is the right project for me. I am very happy to join a strong group, with great players who had a great season last year."
Agent Roberto Calenda made a pointed tweet towards Lazio: "Our choice!"
The Senegal international is effectively the replacement for Kylian Mbappé, who underwent a medical with Paris Saint-Germain today.
The 22-year-old was born in Spain and started out at the Barcelona youth academy, but joined Lazio for a minimal fee in 2011.
He was upgraded to the senior squad in 2013 and last season scored 16 goals with five assists in 31 Serie A appearances, many of them off the bench.
Keita’s contract with Lazio was due to expire at the end of this term and he was frozen out amid this dispute over a renewal.
The Aquile tried to sell him to Milan, Napoli or West Ham United for up to €30m, but he refused and wanted to join Juventus, who were offering only €15m.
Today Monaco also signed Stevan Jovetic from Inter.