Use 4-5-1 V style formation. This is the right counter formation for his 4-1-2-1 Narrow diamond. But ofcourse nothing is a sure win especially if you are over-powered in every angle.

Formation: 4-5-1 V style

----------------------ST----------------------
AML/ML--------------------------------AMR/MR
------------MC---------------MC--------------
--------------------DMC----------------------
DL/DC------DC---------------DC--------DC/DR

Tactics:

Team mentality: Defensive
Focus passing: Down both flanks
Pressing style: Own half
Tackling style: Normal or Hard-(if you can afford a lot of yellow cards and possibly get red cards in return.)
Passing style: Long
Marking style: Zonal

Force counterattacks: Yes
Play Offside trap: No

Arrows:

Blue Arrows: DL,DR,DMC
Red Arrows: AML/ML,AMR,MR
The rest of your players...No arrows.

Goodluck!