I know this has been posted before, but there is about a million threads, and searching the forum I've not gotten a clearcut answer!
I'm facing a Cup match, against an inferior opponent.

He's playing flat 4-5-1

Don't know he's strategy, but based on the last game (ended 0-2 with me away) he got the far most shots, inspite of me having 59 % possession.

I've been using a 3-5-2 V style

It has beeen working so far, until this match. As said before, lost last match 0-2, and meeting him again home in the day after tomorrow. Could really use some advice as to counter that flat 4-5-1. I know it's either a 3-5-2 V or 3-5-2 flat (up the middle), but lacking MR and ML at the moment.
My opponent has a weak DL and ML, and left MC. So it appears focusing on my right side would be good,
I've considered doing the following:

I have a avg. quality of 24, and he's got 21,6.
Doesn't make any sense he wins to me.
Could someone provide some valueable knowledge, and maybe some orders / arrows as well?
Best regards!