Arsenal are still reeling from their shock home defeat to Watford on Tuesday (31 January) but they will have to dust themselves down quickly with a meeting with Premier League leaders Chelsea looming on Saturday.
To make matters slightly more complicated, Arsene Wenger is now wrestling with a full-blown midfield injury crisis. With Mohamed Elneny still on international duty with Egypt at the Africa Cup of Nations, Granit Xhaka still banned and Santi Cazorla still a long-term absentee, options are slim.
Aaron Ramsey has joined that list, limping off 20 minutes into Tuesday's defeat with a calf strain. While the club do not yet know the extent of the Welshman's latest injury, Saturday's trip to Stamford Bridge will surely come too soon for him.
Providing Ramsey doesn't stage a miraculous recovery, that leaves Francis Coquelin as Wenger's only natural central midfield. So who will start against the Premier League leaders?
Alex Oxlade-Chamberlain and Francis Coquelin?
Oxlade-Chamberlain excelled in a central midfield role in the FA Cup fourth round victory over Southampton, spreading balls across the pitch with the vision and poise of a seasoned deep-lying playmaker. The England international dictated the game from midfield, with his short passing equally effective. It's the obvious solution for Wenger. Oxlade-Chamberlain has impressed in that role in previous occasions; scoring twice from central midfield in a league match against Crystal Palace in 2014, returning there away to Stoke City last January where he impressively adapted to a set of fresh demands and responsibilities.
But as is so often the case with the 23-year-old injuries could wreck his plan. The former Southampton midfielder took a kick to the knee on Tuesday night and was visibly limping. Wenger did insists however he did not think it was a big issue.
Alex Iwobi and Francis Coquelin?
The Nigeria international dropped into a deeper midfield role on Tuesday next to Oxlade-Chamberlain with Coquelin acting as an anchor behind the two. Iwobi is deceptively strong and has the ability to link defence and attack with his clever range of passing, but whether he has enough defensively to live with Chelsea's midfield remains to be seen. It's a position he has taken up during his time in Arsenal's youth ranks but he has rarely ventured back since becoming a fully-fledged senior player. Wenger sees Iowbi's long-term future in the No 10 role, a deeper role on Saturday would surely be a last resort.
Ainsley Maitland-Niles and any of the above?
Maitland-Niles was also recently touted as a replacement for Granit Xhaka by Wenger. The 19-year-old was given the nod to partner Oxlade-Chamberlain in that 5-0 thrashing of Southampton, the latest in a growing list of positions he has been deployed in this season. Maitland-Niles started his season at right-back, where he spent much of last season on loan at Ipswich Town, taking up that role in the EFL Cup third round against Nottingham Forest before moving into a defensive midfield role in the fourth round against Reading.
Wenger opted to use him in a similar fashion in the FA Cup, filling in on the right hand side of defence against Preston North End before so effectively partnering Oxlade-Chamberlain at St Mary's. "Maitland Niles has played a lot on the flanks but I have seen qualities in him that tell me he can be useful in the middle and he can also be a defensive specialist," Wenger noted afterwards. With stern stuff required at Stamford Bridge, Saturday could be a huge opportunity for the teen.
Since losing Xhaka to that four-match ban, Wenger has also named checked Jeff Reine-Adelaide as an option to provide cover in central midfield. A surprise call up for Gedion Zelalem is out of the question; he departed on transfer deadline day to join VVV-Venlo on loan until the end of the season. So did Ismael Bennacer, who had played in a deeper midfield role for the club's Under-23s this term, he will spend the remainder of the season in France's second tier with Tours FC.