"He has great potential. He's really smart, a guy who's always thinking," Ruben Amorim said after Benjamin Sesko's £74 million ($101m) switch to Manchester United from RB Leipzig at the start of August. "He can play a different type of football. He is going to feel that the Premier League is aggressive. He is going to learn. But Ben can be a striker for United for a lot of years; that's why we paid so much money to have a striker who will have his history in our club."Unfortunately, that potential has not shone through in his first seven games for the Red Devils. Sesko went six games without scoring, albeit while only starting two, before finally getting off the mark against Brentford at the Gtech Community Stadium last weekend - bundling home from close range at the third time of asking.And while that effort was no doubt a moment of relief for the 22-year-old, it ultimately counted for absolutely nothing. United ended up losing the game 3-1 and slipping to 14th in the Premier League table - just one place higher than where they finished last term.Despite the presence of Sesko, and fellow summer signings Matheus Cunha and Bryan Mbeumo, consistency and goals are still elusive for Amorim's team. Indeed, that trio has only scored three between them from 20 combined appearances across all competitions. It's obviously still very early, but that is an awful return considering the club's £208m ($280m) investment in their services.Sesko's numbers are not the biggest concern, though. Unlike Mbeumo and Cunha, who have shown plenty of industry on the ball, the Slovenia international has largely stood on the periphery struggling to impose himself. The learning curve wasn't supposed to be this steep. But much of the blame for that must be laid at Amorim's door. United are not even trying to play to Sesko's strengths, and at the moment, he's facing an impossible task as the lone striker in a deeply flawed system.