Arsenal manager Arsene Wenger could be without Mathieu Flamini and Serge Gnabry for Tuesday's League Cup clash with Chelsea.
The former - who has been a regular fixture since re-joining from Milan in the close-season - is unlikely to play a part having sustained a groin injury against Crystal Palace on Saturday.
Flamini was forced off the field after just eight minutes in Arsenal's 2-0 win, with Wenger now facing an anxious wait to determine his availability.
"He has a scan today and then we will get the results as to how long he will be out," he said.
"It doesn't look like a bad muscle injury but honestly it's too early to give you a precise answer. It's a groin injury."
Wenger could also have to make do without teenager Gnabry - who signed a new long-term contract on Monday - can play a part in the fourth-round encounter.
The German replaced Flamini at Selhurst Park, but also picked up a knock.
"Serge Gnabry has a problem, he got a kick on the ankle. He will be assessed tomorrow (on Tuesday) ," Wenger added.
"After that we will decide who plays and who doesn't play."
Wenger confirmed that Jack Wilshere is fit and available, but the England midfielder could be rested, with the Arsenal boss also revealing he is set to pick a rotated side for the game at the Emirates Stadium.
|Coach: A. Wenger|
for R. Miyaichi 63'
for N. Bendtner 67'
for A. Ramsey 81'
|Liverpool can make Champions League, says fanzine editor|
|Walsh: Hull clash crucial for Leicester|
|Toure, Aubameyang and Enyeama make shortlist for African gong|
|Docherty backs Chelsea to win two-horse race|
|Liverpool could benefit from Hyypia influence - Scales|
|Saudi Arabia name Asian Cup squad|
|Forty-year-old Cahill no problem for Postecoglou|
|Wenger criticism baffles Redknapp|
|Leicester must strengthen in window - Walsh|
|United not title contenders - Docherty|
|Koeman: Southampton youngsters will get a chance|
|Dyche empathises with Liverpool striker crisis|
|Cagliari turn to Zola|
|Rooney thanks Van Gaal for Christmas break|
|Cruzeiro offer Paulinho Tottenham exit chance|
|Carlisle´s wife grateful to Burnley|
|Katebe called up to Zambia AFCON squad|
|Cape Verde name AFCON squad|
|Finke names much-changed Cameroon squad|
|Grant omits World Cup troublemakers for AFCON|
|Blackpool striker Ranger goes AWOL|
|Allardyce relishing Mourinho meeting|
|Ashley fails to increase Rangers stake|
|Crystal Palace v Southampton: Koeman calls for focus|
|Warnock targeting striker in January|
|Chelsea v West Ham: Adrian vows visitors will attack|
|Heskey signs short-term deal at Bolton|
|Everton v Stoke City: Martinez eyes strong form|
|Juninho defends David Luiz|
|Burnley v Liverpool: Dyche defends Rodgers ahead of Turf Moor test|
|Arsenal v QPR: Wenger eyes festive momentum|
|Liverpool are growing in confidence, says Rodgers|
|Redknapp: Austin future could depend on survival|
|Martinez wants Everton consistency|
|Barca want Neymar until 2020, says agent|
|Jones undeterred by pressure of Liverpool starting role|
|Allardyce ´knows how to beat managers´ - Carroll|
|Jones playing for a new contract|
|China select Evergrande spine for Asian Cup|
|A-League Preview: Koren tips City to build|
|Khedira keen to fight for Real spot|
|Southampton confirm Elia deal|
|Cellino to remain as Leeds owner until after appeal|
|Manchester United v Newcastle United: Van Gaal demands domination|
|Van Gaal refuses to dismiss Bale speculation|
|Sunderland v Hull City: Bruce sure of Hull revival|
|Swansea City v Aston Villa: Lambert optimistic of away success|
|Agbonlahor red rescinded|
|Falcao depends on team-mates to perform - Van Gaal|
|Monk dismisses talk of Gomis move|
|West Brom v Manchester City: Pellegrini to experiment again|
|Xavi: I was ready for New York switch|
|Ibrahimovic fumes at awards snub|
|Irvine: No approaches for Berahino|
|Pearson determined to revive Leicester fortunes|
|League Two Preview: First host third as Wycombe meet Luton|
|League One Preview: Buoyant MK Dons eye more glory, Bristol City seek response|
|Championship Preview: Pritchard plotting to end Ipswich run, Bournemouth host Fulham|
|Kaboul place not guaranteed by captaincy - Pochettino|
|Koeman hopeful of Elia deal|
|Atletico president not ruling out Torres return|
|Swansea secure Oliveira signing|
|No excuses for Pellegrini|
|Walcott pace unaffected by injury|
|Former Real Madrid star Roberto Carlos backs Ronaldo for Ballon d´Or|
|Former PFA chairman Carlisle ´stable´ after serious incident|
|Balotelli remorse saved him from longer ban|
|Bayern midfielder Martinez ´on track´ with rehab|
|Pardew ´overjoyed´ at Gutierrez return|
|Spurs confirm Yedlin to join in January|
|Zeman sacked by Cagliari|
|Casillas: I´m going nowhere|
|Bruce demands McShane apology|
|Pulis would welcome Brighton talks|
|Buffon: Juve angry after Supercoppa loss|
|Arteta out until new year|
|Rangnick: Kampl deserves Dortmund switch|
|PFA offers support to Carlisle after serious incident|
|Napoli can mount title bid - Higuain|
|Cech´s agent urges Liverpool and Arsenal to make bid|
|Hart happy to be back to his best|
|Terry thrilled with ´revelation´ Matic|
|Perez rues ´unfair´ Tyne-Wear derby result|
|Khalfan Ibrahim returns from injury|
|Magath slams ´sensitive´ Fulham|
|´Limited´ attacking options inspire Postecoglou´s selections|
|Carlisle reportedly involved in serious incident|
|Primeira Liga Review: Braga leapfrog Guimaraes|
|Hughes upbeat despite Stoke defeat|