You can call it whatever you want but she absorbed the sporting director role into hers since 2017. And we've all seen what that have led to in the transfer market. Now, maybe it was Roman who made that decision or maybe it was Marina (they clearly work closely together) but it was one sh*te decision either way to not get a replacement for Emenalo.
She's been in charge of running the club for a long period of time right now. What has she done that's that great?
Do we have a good wage structure? No it's shambles.
Do we have a good transfer structure? No it's shambles.
Do we have a good scouting structure? See above
Have we done great commercially during her reign? No we have fallen behind our competitors here too.
Have we competed for Premier League titles since 2017? Not even close once.
What excactly has she done that's great?
Not quite. The sporting director role was split with more responsibilities going to the managers and scouting departments.
Since Emenalo's departure it's pretty much worked like this - manager reports on what he wants, scouting identifies potential targets, manager picks preferences, Marina finds out which of those targets are doable/feasible tries to get it done.
Wage structure - it's as good as can be expected given how much we've won over the last 18 years. It only looks poor given recent transfer failings.
Transfer structure - not bad, but severely impacted by short-termism culture under Roman. Not much different from the structure in place at City (acquisitions aside).
Scouting structure - pretty much the same as it has been for a long time.
Commercial success - Nothing to do with Marina, but we're fine here too given the club size and reputation.
She's had some very good dealings with incomings and outgoings (specifically related to her role) - Luiz, Hazard, Havertz, Kante to name but a few. And pretty much been the best selling club during her tenure.
But instead of me telling you what she's done that's been great, you can instead read some quotes from people who have actually worked with her - on both sides of the table.