Chelsea have agreed a £38m deal with Monaco to sign the France defender Axel Disasi after losing Wesley Fofana to a serious knee injury. Disasi will provide extra competition at centre-back and is due to discuss personal terms before completing a move to Stamford Bridge. Chelsea, who are also weighing up a move for the Brighton & Hove Albion goalkeeper Robert Sánchez, have been forced into the market for a defender because of Fofana’s injury and have moved swiftly in negotiations with Monaco. Chelsea’s co-sporting director, Laurence Stewart, was hired from Monaco this year and knows Disasi well. The former Reims centre-back is regarded as one of the biggest talents in Ligue 1 and was part of France’s World Cup squad last year. The arrival of the 25‑year‑old could increase the possibility of Trevoh Chalobah leaving Chelsea. Internazionale and West Ham are thought to be interested. With Fofana potentially out for the season after having knee surgery, Chelsea’s options in central defence include Thiago Silva, Levi Colwill, Benoît Badiashile and the inexperienced Bashir Humphreys. Badiashile was signed from Monaco in January and also knows Disasi well. Humphreys is likely to go on loan. The club are considering a move for Sánchez as they hunt for a keeper who can provide competition for Kepa Arrizabalaga. Sánchez has fallen out of favour under Roberto De Zerbi, who replaced him with Jason Steele last season and Brighton could be tempted into a sale after signing Bart Verbruggen from Anderlecht. Chelsea are monitoring the situation and are expected to bid for the Spain international. Mauricio Pochettino is keen to sign a goalkeeper this summer and Chelsea did explore moves for André Onana, who ended up joining Manchester United from Inter, and Milan’s Mike Maignan. But Chelsea have decided not to spend big on a new No 1 after failing to find a buyer for Arrizabalaga. They are prepared to compromise by bringing in experienced cover for the Spaniard after the sale of Édouard Mendy to Al-Ahli. Arrizabalaga has competition from Marcus Bettinelli, Lucas Bergström and Jamie Cumming. Chelsea are poised to loan the promising American teenage goalkeeper Gabriel Slonina to KAS Eupen in Belgium. Sánchez would not be expected to cost as much as Onana or Maignan. The 25-year-old broke into the Brighton side under Graham Potter but lost his place under De Zerbi. He has not been part of the club’s pre-season tour of the US and is likely to need a new challenge. Chelsea have already been in talks with Brighton over Moisés Caicedo. They have had multiple bids for the midfielder rejected, with the latest worth £80m. Brighton are demanding £100m for the Ecuador international, who wants to move to Stamford Bridge, and have asked Chelsea to include the 20-year-old centre-back Colwill as part of the deal. They could look at alternatives and are poised to complete the £23.5m signing of the 19-year-old Rennes midfielder Lesley Ugochukwu, who could be loaned to Strasbourg initially. They hold a strong interest in Southampton’s Roméo Lavia, but Liverpool are favourites to sign the Belgian midfielder. Southampton want at least £45m for Lavia. Chelsea remain interested in signing a striker to compete with Nicolas Jackson and have made initial inquiries about key targets. They are also pushing for reinforcements in attacking midfield, including Ajax’s Mohammed Kudus. They are interested in Crystal Palace’s Michael Olise, Lyon’s Rayan Cherki and Celta Vigo’s Gabri Veiga, who has a £34m release clause.