LONDON -- Marcos Alonso has signed a new contract at Chelsea that keeps him at Stamford Bridge until June 2023.
Sources told ESPN FC on Tuesday that Alonso would commit to a new deal which puts him on significantly improved financial terms.
"I am so happy to stay here longer and to keep playing for one of the best teams in the world," Alonso told Chelsea's website. "It's been a very good two seasons and I am looking forward to more."
Speaking to Spanish newspaper AS earlier while on international duty in October, Alonso revealed that talks over an extension had reached an advanced stage and that he expected to put pen to paper by the end of the month.
Alonso was a relatively unheralded signing for Chelsea, in a £24 million deal from Fiorentina, in August 2016 but has established himself as a key contributor, operating effectively at left wing-back under Antonio Conte and transitioning well to the left of a back four since Maurizio Sarri's arrival at Stamford Bridge.
Sources have told ESPN FC that several European clubs enquired about Alonso's availability last summer, but once Sarri made it clear that the Spaniard was key to his plans, Chelsea's priority became committing him to a new long-term deal.
Sarri has spoken highly of Alonso on several occasions this season and relied upon the 27-year-old so heavily that January signing and Italy international Emerson Palmieri has been limited to just two appearances in all competitions.
"Alonso, at the moment, in this position at left-back is maybe the best in Europe," Sarri said in September. "[His] physical qualities are at a top level, I think. He's doing very well in the offensive phase. But I also think he can improve in the defensive phase. If he improves that, he could be the best left-back in the world."
This new long-term deal follows the one-year extension granted to Pedro Rodriguez in August, but Chelsea still have plenty of contractual uncertainty to navigate in the coming months when it comes to their senior squad.
Top of the priority list is Eden Hazard, who for the moment remains inclined to keep his options open after admitting earlier in October that joining Real Madrid remains his "dream" and he wants to "make it happen", though he also stressed that he is open to talks over a new contract at Stamford Bridge.
Chelsea are desperate to keep Hazard, whose current deal runs to June 2020, and sources have told ESPN FC that they are prepared to make him the highest-paid player in the club's history as part of any long-term extension.
David Luiz, Olivier Giroud and Cesc Fabregas are all set to be free agents next summer and would like to remain at Stamford Bridge beyond this season, but club captain Gary Cahill looks set to leave after making it clear that he will seek more regular first-team opportunities elsewhere in January.