This is a good step from Marseille considering that the results they got last season were not good, only being ranked 8th in the Ligue 1 standings, even though the previous season they were in the top 3 of the standings. Mason Greenwood is also still young (22 years), this could be a double advantage for Marseille, on the one hand they get a new striker to add to the squad, especially on the front line, and on the other hand it's a long-term investment, last season with Getafe he was successful made 10 goals & 7 assists from 30 appearances, not bad at all.
Not only did they finish in a bad position, because Marseille may also have been a worse team last season because they failed to finish in a better position than Lyon, who previously had bad results at the bottom of the standings. With results like that, of course Marseille really needs to make improvements regarding better players in every line to be able to make Marseille get better results in every match. Although indeed, we also cannot fully believe that Mason Greenwood will have a great impact for Marseille.
I also noticed something strange, I thought Marseille were at the bottom of the standings at the start of the season and because of that getting 8th in the standings was not a bad thing, it turns out I was wrong, that it was not Marseille but Lyon. I think these reasons are enough for Marseille, they have to improve, they have to make the team return to the Marseille that people used to know.