Chelsea's hopes of retaining the Premier League title seem to be already over following an unproductive summer transfer window at Stamford Bridge.

Antonio Conte reiterated during the summer that the Blues needed to add depth to their squad to compete on four fronts but many of his requests were ignored.

Chelsea sanctioned the departure of Nemanja Matic to Manchester United and sold Diego Costa to Atletico Madrid to bring in two younger players in the form of Alvaro Morata from Real Madrid and Tiemoue Bakayoko from Monaco.

Targets such as Alex Oxlade-Chamberlain and Fernando Llorente moved to Liverpool and Tottenham Hotspur respectively while Danny Drinkwater and Davide Zappacosta only joined Chelsea on deadline day.

Conte's complaints has been vindicated during the opening part of the season with the Premier League holders trailing Manchester City by 14 points after 21 games.

Chelsea can still fight for the FA Cup, the Carabao Cup and the Champions League but some reinforcements will be much needed to avoid a season without silverware.

What they need:

Marcos Alonso has impressed since his arrival from Fiorentina but Conte doesn't have a single player in the squad to cover the Spaniard in case of emergency.

Something similar happens with Cesc Fabregas. The former Arsenal and Barcelona playmaker has managed to resurrect his career at Chelsea to become a key player in Conte's new 3-5-2 formation with an extra man in the middle of the field and only two forwards.

Yet, there is no one else in the squad with his creativity and every time the Spaniard is absent the Blues miss him desperately.

Meanwhile, in attack, Conte would welcome a number nine to serve as Morata's back-up having shown during the first-half of the season that he barely trusts in Michy Batshuayi.

Furthermore, the signing of a world-class centre-back will also become a priority if David Luiz finally leaves the club.

Who could join:

Alex Sandro
Alex Sandro was already poised to join Chelsea in the summer. Getty

It is said that Conte remains keen on signing Juventus wantaway full-back Alex Sandro but the Blues may face competition from United, with The Mirror recently claiming that Jose Mourinho is considering a £60m offer to win the race for the Brazil international.

The Premier League champions are also said to be ready to battle with Liverpool for the signing of Monaco star Thomas Lemar, while the speculation linking them with Ross Barkley continues after a £35m deal to sign the Everton midfielder in the summer fell through on deadline day.

Bayer Leverkusen star Leon Bailey is also on the Blues' radar while Conte recently underlined his admiration for Bayern Munich star Arturo Vidal.

Who could leave:

Luiz's future at Chelsea has been under major scrutiny since Conte left him out of the squad for the 1-0 victory over Manchester United on 5 November.

Real Madrid, Barcelona and Newcastle United have been linked with his services while recently The Sun reported that Arsene Wenger is planning to launch a £25m bid to lure the Brazilian to Arsenal.

A January exit could be a good solution for all parties as his big-money sale could help fund the pursuit of Conte's other targets.

Batshuayi is also said to be considering his future at Chelsea but it seems unlikely that Conte will let him go without first signing a replacement.

Elsewhere, the likes of Charly Musonda or Kenedy could move on loan having barely played during the opening part of the campaign.

What the manager has said:

Antonio Conte
Conte's Chelsea will learn their fate when the last 16 draw takes place on 11 December. Getty Images

"I give my opinion when I speak with my club but the club always has the last word," Conte recently said when asked about the Blues' January transfer plans. "Like in the summer and it will be the same in January and then we divide the responsibility between me and the club. Not only me, not only the club, but together.

"I am very happy to work with my players, then if the squad is big enough to play in all the competitions? Only time will tell this. If we have to work as we are in the Champions League, semi final of the Carabao Cup and we are fighting for the best position in the league. I think we are doing a really good job with my players."