Unai Emery has explained why Jadon Sancho was not included in Aston Villa's squad to face Everton on Sunday evening. Sancho joined the Villans on loan from Manchester United in September but has struggled for regular game time at Villa Park. Indeed, he has started just two league matches this season, with the majority of his minutes coming in the Europa League.Speculation over the weekend has linked Sancho with a return to Borussia Dortmund for a third spell with the German side. Sancho moved to the Bundesliga powerhouse from Manchester City back in 2017 and established himself as a key man.United parted ways with a reported £73 million ($97m) to lure the winger back to Manchester in 2021. However, Sancho failed to replicate his Dortmund form at Old Trafford, and returned to Signal Iduna Park for a brief spell in 2024 after being ostracised by then-United head coach Erik ten Hag, ultimately playing a key role in BVB's progression to the Champions League final.The 25-year-old spent last season on loan with Chelsea, who chose not to exercise their option to make Sancho's move permanent, paying United a £5m penalty in the process.Sancho's current United deal expires in the summer, with a third Dortmund spell reportedly on the cards when he becomes a free agent.Sancho will see out the season with Villa, though he missed out on the matchday squad for the home game against Everton. However, Emery has clarified the reason the forward didn't make the cut against the Toffees.When asked by Sky Sports why Sancho missed out on Sunday, Emery replied: "He is sick."The Villans fell to a surprise 1-0 home defeat to David Moyes' side, with Thierno Barry's second-half strike the difference between the two sides in the Midlands. Both Pau Torres and Emiliano Martinez were at fault for the 23-year-old's fourth league goal of the season.The result means Villa have now won only one of their last four league games and it leaves them seven points behind league leaders Arsenal, after the Gunners were held to a 0-0 draw with Nottingham Forest on Saturday.Looking for smarter football bets? Get expert previews, data-driven predictions & winning insights with GOAL Tips on Telegram. Join our growing community now!Everton, meanwhile, moved up into 10th in the table following their triumph at Villa Park, as they bounced back from their disappointing FA Cup third round exit at the hands of Sunderland last weekend.The victory is all the more impressive given Everton's raft of absentees. While the Merseyside club welcomed Jack Grealish back from a ban to face his former side, the Toffees were without eight players for Sunday's narrow win, including the suspended Michael Keane, and injured quartet Charly Alcaraz, Seamus Coleman, Kiernan Dewsbury-Hall, Jarrad Branthwaite and Tim Iroegbunam. Idrissa Gueye and Iliman Ndiaye are with the Senegal national team for the Africa Cup of Nations.Moyes has admitted that his Everton side "need more players" with a little over two weeks to go until the January transfer window closes."The reality hasn’t changed. We’ve said all along, we’re looking, we’re trying," Moyes said before the game. "It’s not like we’ve shut ourselves off from the transfer window. We need players more than ever and we probably need them as soon as possible if we could make that happen."But more than likely, this month is never done particularly quickly, so we’re still looking. I’m not sure we will get anything but we’re trying."Add GOAL.com as a preferred source on Google to see more of our reportingSancho will hope to make a full recovery from illness and return to Emery's squad for Villa's next game: an away clash with Fenerbahce in the Europa League on Thursday. Villa will be back in Premier League action at Newcastle three days later, while Everton are set to face Leeds at Goodison Park on January 26.