Monaco agreed a loan deal for influential Fulham striker Dimitar Berbatov late on Friday, hours before the January transfer window closed.
The former Manchester United, Tottenham and Bayer Leverkusen forward has joined Claudio Ranieri's Principality side until the end of the Ligue 1 season.
Berbatov, 33, arrives at Monaco as a stand in for Radamel Falcao, the Colombian star striker who is facing months on the sidelines after suffering a serious knee injury.
Monaco are lying second in the table, six points behind Paris Saint Germain after the capital club's 2-0 win over Bordeaux on Friday.
Monaco can reduce their deficit on PSG with victory at Lorient on Saturday.
Bulgarian forward Berbatov joins the ligue 1 outfit after scoring five times for struggling west London side Fulham this season.