Fresh off a grueling 120-minute slog versus Wigan, Arsenal will host London rivals West Ham in a game they absolutely need to win in order to keep the race for fourth place alive on Tuesday.
That means Arsene Wenger will have to be very calculating and shrewd in his use of the very few resources at his disposal.
He revealed in his pre-match press conference that many players' involvement is very uncertain, and even some of those involved last weekend might be unavailable for this crucial tie. Tomas Rosicky and Laurent Koscielny may or may not start, while Nacho Monreal, Aaron Ramsey and Lukas Podolski are all nursing strains and aches from the semifinal.
That, plus an injury list that already includes Jack Wilshere, Abou Diaby and Mesut Ozil makes for quite the selection dilemma. Note that Mathieu Flamini is also suspended.
This is one of those relatively few times when anything you or I speculate here is extremely fallible and is indeed likely to be wrong. Much depends on very late fitness tests and game-time decisions, plus whatever tactics Wenger might employ.
Nevertheless, let's posit a best guess.
This line-up contains a few no-brainers and a few highly debatable and questionable decisions.
Wojciech Szczesny, Bacary Sagna, Per Mertesacker, Kieran Gibbs and Olivier Giroud are all certain to start. The first three because they are some of Wenger's most trusted servants (and he might not have a choice at left-back) and the latter because he did not play the full 120 minutes last weekend.
Lukasz Fabianski would obviously not be a bad choice to continue in goal after his heroic display against Wigan, but Wenger has seemed content this season to let him handle the cup while the long-term No. 1 Szczesny plays in the Premier League.
Now for the thornier parts.
I assume that Koscielny will be fit enough to play, as Wenger implied in his press conference that the Frenchman is one of the closest players to recovery. And Wenger has consistently shown this season that, if Koscielny's legs can handle it, he will play him alongside Mertesacker in central defense.
In midfield, Kim Kallstrom is likely to get his first start for Arsenal because he only came on at the tail end of the semifinal and there are no other fully fit and rested options.
If Rosicky is fit enough to start, perhaps Kallstrom will be the only defensive midfielder in red and white. Hopefully that is the case; Mikel Arteta played the full 120 and had seemed to be slowing down even before last weekend.
But I'm playing it safe and assuming that the Czech won't be fit to start. In the absence of the suspended Flamini, Arteta is the only man left.
Santi Cazorla will also be forced to start despite fully exerting himself against Wigan in the absence of alternatives. It's unfortunate, but Wenger really has no other choice since Ramsey is knackered and Ozil is still out.
Alex Oxlade-Chamberlain is a similarly unfortunate inclusion, but who else is there to start on the right flank?
This squad really is stretched to its limit but hopefully will be able to overcome its undoubtedly crippling fatigue in time for injured players to return and ease the pressure.