How to win against 3-3-2-2

I need to win against DC DC DC
MC MC MC
AML AMR
FC FC

I usually use a similar formation DR DC DC DL and with this I won the league in last two seasons even had 15 points more
MC MC
AML AMR
FC FC

than second placed team last season, but this season I lost against team using this tactic and no one else in my league is even close to beating him even though I won all my other league games. He is 3 star better than me on average but that's not really much. Any thoughts?

I should attack on flanks, seems obvious but which tactic should I use?