Chelsea's 2-0 victory over Everton in the Premier League has been overshadowed by injury concerns surrounding Emiliano Martínez.

The Blues were dealt a major blow midway through the second half as Martinez was stretchered off and replaced by 21-year-old Mike Penders.

The 34-year-old clashed with Everton’s Jarrad Branthwaite after both players attempted to play the ball from a free kick delivered by the home side.

The west London side managed to see off a tepid response from the hosts, and Pedro Neto’s second strike of the afternoon ensured Chelsea would be heading back to Stamford Bridge with all three points.

Naturally, concerns continued post-match, with reporters questioning Xabi Alonso about the latest developments regarding the Argentine goalkeeper.

Immediately after the full-time whistle, he said: “What we know is that he left the stadium conscious, and right now he’s in the hospital undergoing precautionary tests.”

Since then, the goalkeeper has undergone those tests and, according to Argentine journalist Gastón Edul, scans on his back and neck reportedly showed no issues.

However, further tests have also revealed that Martínez has suffered a jaw injury and will now require surgery. This is expected to keep him on the sidelines for the foreseeable future, with no timeline yet established for his return. 

Martínez's injury is likely to give Penders an opportunity to establish himself as Chelsea's first-choice goalkeeper. With three weeks still until the next international break, he will likely be between the sticks for Chelsea’s remaining matches in October. These include back-to-back home Premier League matches against Tottenham and Manchester United, with a trip to Liverpool sandwiched between them in the League Cup.

Having only just emerged from an injury crisis that affected the Blues before the 3-0 defeat to Brentford, which saw João Pedro, Reece James and Moisés Caicedo sidelined, it seems that luck is still against Alonso and his side.

Chelsea's injury concerns continue to mount. James is expected to remain sidelined until the new year, while Jamie Gittens is yet to return to team training and Emmanuel Emegha continues his recovery. Pep Chavarría also picked up a knock the day before the trip to Merseyside, further reducing the options available to Alonso.

The Blues currently have enough options across the pitch in several areas, but they are now running thin on quality, depth, and experience in wide areas and in goalkeeping. 

Although Penders is highly regarded and viewed as a potential long-term number one at Stamford Bridge, he still lacks experience. The match against Tottenham on October 24 is expected to be his first Premier League start.

It is expected that either Teddy Sharman-Lowe or Gaga Slonina will deputise for Penders while Martínez works his way back to a full recovery.

Chelsea provided an update of their own on Sunday morning, confirming that the goalkeeper had undergone surgery.

The statement read: "Goalkeeper Emiliano Martinez has undergone successful surgery on a fractured jaw.

Martinez was injured following a collision midway through the second half of our 2-0 victory over Everton at the Hill Dickinson Stadium on Saturday.

Martinez was taken to hospital for further assessment, which confirmed a fractured jaw that required surgery.

Everyone at Chelsea wishes Emi a speedy recovery and will support him throughout."