When did we face Sarri?
You might be right but as you alluded to, Lampard will need to do that consistently to be a top coach. Doing it for one game here and there doesn't cut it, does it? I mean, any average manager can have their day. Hodgson, for example, has masterminded some excellent wins against the big teams with smaller teams but you wouldn't say he's a top coach would you, especially after his time at Liverpool?
Also IIRC, you said that Mourinho is basically a yesterday manager, a manager past it (or something along those lines) and if so, not sure what's the weight here that Lampard managed to out thought him. The performance and win at Ajax were good, I'll say that, but as I mentioned it back then, Ajax have a poor recent home record in the Champions League. It was their away form that got them to the semis last season.