The must-win group match - to be played without injured stalwarts Milos Ninkovic, Bobo and Michael Zullo and the suspended Brandon O'Neill - will be the first since Arnold was confirmed as long-term Socceroos coach last week.
History suggests distraction of this kind has a tendency to undo teams - even those used to being on top.
But Arnold, who has pledged his commitment to Sydney until the end of this season, stressed nothing will change for his defending A-League champions.
"This type of situation is unique to me, there's no doubt about it," Arnold said.
"But it's the situation I'm in at the moment, and it's one I will take total control of and make sure there's no distractions to players, staff or the club around what we will do.
"It's about commitment to each other ... the whole focus is on the team until the end of this season.
"Then, if there's any other decisions to be made from the players or from the club, they will be made at the end of the season.
"Until then we have the Champions League to contest - we plan to stay in the group phase - and we are ready to win the (A-League) premiership and the grand final."
With a single ACL point from their opening three group games, a third loss for the last-placed Sky Blues will almost certainly spell the end of a continental campaign many initially believed could go all the way.
Last week's 2-0 home loss to Group H leaders Kashima suggests the J-League heavyweights will be an even tougher a prospect at home in Japan.
And that's before factoring in who's missing.
Key attacking prowess is lost through the absence of star playmaker Ninkovic (hamstring) and A-League golden-boot leader Bobo (back), both left at home to recover in time for Saturday's A-League clash with Brisbane.
Left-back Zullo is still another fortnight away after re-injuring his hamstring last week and, with midfield mainstay O'Neill completing the quartet of non-travellers, Arnold will be forced into the most changes he's made all season.
Yet he remained confident Sydney could return with three points and something to play for in their two remaining group games against Suwon Bluewings and Shanghai Shenhua.
"It's just about ... taking those opportunities when you get those big moments," Arnold said.
"We haven't done that the last three times but I expect that will happen tomorrow night."