We shouldn't be selling luxuries, especially if it gives us tactical flexibility. We may not have oil money, but we certainly aren't poor anymore. You win by having such players.
The final against Madrid, for example. Look at our subs vs theres.
Do you think a 4-3-1-2 would work? With Mandzukic and Ronaldo up front with Dybala at trequartista? I hate having him benched, he can win a game on his own with ease.