It seems like only yesterday that Arsenal were in the last round of the Cup, doesn't it? Well, it wasn't yesterday, but it was just a few days ago that Arsenal destroyed Hull 4-0 in the fifth round replay to advance to this game, a home tie against Watford that will send the winner to the semifinal on either the 23rd or 24th of April.
Arsenal hobble into this game easy winners, but heavy losers in the "let's stay healthy" part of the competition; Per Mertesacker, Gabriel, and most worryingly, Aaron Ramsey's injuries in Tuesday's replay put a big dent in Arsenal's depth heading into a busy few weeks.
Mertesacker's injury is probably the least severe - he has what Wenger terms "a little concussion", which, hmmm. Gabriel has a hamstring injury, and Ramsey has a "thigh strain" of uncertain severity. I would say that, given England and soccer in general's disregard of the seriousness of anything concussion-related, Mertesacker will play if possible, but the other two are a pretty big question mark.
Watford's route to this round was much more straightforward - they beat Leeds 1-0 at Vicarage Road. They did lose 1-0 to league leaders Leicester last weekend, but they also managed to come through said match unscathed, which means that 13th placed Watford will probably throw everything they can at Arsenal, since the FA Cup is their only chance of silverware this season; Arsenal's chance at the League isn't much better, but it's a chance, and with a lot of players missing, the subs/reserves will have to be firing on all cylinders on Sunday.