Well we were two down at that point and he had already switched the formation back to usual by bring Sanchez on. Fellaini as the masterplan when we're losing has been a problem we've had for far too many years now.
The system that we started with was what I was referring to and I think the system he wants to play this year judging by what he has been saying about needing another centre back and formations in pre-season is 5 at the back with the wingbacks providing support, Pogba, Matic Fred in midfield with Lingard/Sanchez/Rashford behind Lukaku. Fred and Lingard provided the energy and the pressing and Spurs struggled with it for the first half hour and we actually looked somewhat fluid in our football (seldom can that be said) just unfortunately it wasn't sustained. (Probably due to the number of players starting their first game, the amount of changes, 6 players brought in, the sudden tactical switch, playing a player out of position).
It was completely different to what anybody was expecting, I for one was expecting a tight dogged performance with a very narrow midfield and Herrera basically man marking Erikson or Ali. The problem with the system is that at this point in time we don't have the players for it, although the same can be said of our 4-3-3 where we lack a right winger and use Mata instead and the left wing is a rotation of underperfoming players in Sanchez, Martial and Rashford.
I personally felt the style of football was better, more befitting of United and that he just needs to stick with it rather than chucking it away to grind out results, one of the reasons United fans are so tired of him. I still can't quite fathom how we haven't strengthened our defence though over the years as you think back to the Van Gaal game at Leicester where our weak defence was brutally exposed and yet years later here we are talking about pretty much the same personnel being poor.