#1 advice for all achievements in this game: Set the difficulty to easy from the Options menu and choose easy difficulty in Competition.
Go into Competition and select Super League. Pick "Leeds Rhinos" as your only "Player" or team and begin the season. Simulate every match and one of this team's players should get the Man of Steel award towards the end of the season. It is not necessary to win the grand final with this team. In my case, the simulation resulted in a loss in the quarter final and that was the moment one of the players in this team received the Man of Steel award. It might take a few tries, I am not sure as I got it on my first try using this strategy.
This achievement doesn't seem to unlock if you simply choose to control all NRL/SL teams and simulate every match till the end of the season.
Source for this information: https://www.playstationtrophies.org/forum/1907636-post21.htm...