The reasons why Arsenal face an uphill struggle at the Allianz Arena tonight are easy to pinpoint. They are 3-1 down from the first leg, away from home, and are missing Jack Wilshere, Lukas Podolski, and Wojceich Szczesny, not to mention their two first choice full-backs.
Which means if they are to have any chance whatsoever, they need their top attacking players to show up.
This means Theo Walcott, who has gone strangely off the boil over the past few weeks, and has oddly ineffective in the first leg.
Yet rumours are circulating that Arsene Wenger will start him on the bench along with Cazorla, effectively giving up on the tie, but if he comes on he will want to have a big impact.
Walcott needs to change his fortunes, and this game on the big stage in front of a watching Europe is his chance to impress. He will desire to be involved and get back in among the goals.
The Englishman put his club and supporters through the wringer earlier this season, allowing his contract saga to drag on right from last summer until mid-January without any resolution.
So is it just a coincidence that ever since January 30, when he netted against Liverpool in a 2-2 draw at the Emirates, that his goalscoring touch has deserted him?
Not entirely. Central to Walcott's contract saga were his demands to play up front as a striker, but ever since he has been shunted back out the the right wing - with no goals to show for it in six matches.
There is no reason why he shouldn't score from out wide, he netted four times early on in the season from the wing before Wenger started playing him up front, and scored 11 from the wing last season.
Which begs the simple question, is Walcott out of form, or simply throwing a bit of a sulk that he isn't starting up front?
Well he can't be happy that manager Arsene Wenger has kicked him aside for Olivier Giroud the second he signed on the dotted line, but the problem is Giroud also hit form in mid-January, and does not have the versatility Walcott offers to play out wide.
Wenger has stayed steadfast to his tactic of playing only one striker, leaving Walcott left out wide.
The manager has to therefore decide whether to change his recent tactics around. And if he wants results this means trying Walcott up front again rather than out wide, or on the bench.
But if not, Walcott has to look in the mirror and ask himself if there is anything he needs to get back to doing, to start chipping in with goals again, because if ever Arsenal needed Walcott to step up and earn his repored £100,000 a week wage, it is tonight.
What is behind Walcott's lack of goals lately? Purely a loss of form or is he throwing a sulk?
image: © Ronnie Macdonald