Thanks for noticing the backtracking, deleted it.
I think it's incorrect to compare De Hea and Marcial, precisely because as you correctly wrote the last couple of years Marcial hardly played at all, was often injured and had no significant impact on the team's play, unlike De Hea who left as a strong top goalkeeper.
Even now Manchester City fans are making video clips of De Hea when he played in the Fiorentina goal against Accademia Puskas and saved Fiorentina from a goal several times, all after 18 months out of action!
So we can say that David De Hea is really a unique man who was able to find his strength after 18 months without soccer and thanks to his game Fiorentina reached the main tournament of the conference league.
This is the thing I guessed you got me wrong while De Gea was a top goalie before his contract ran out at Manchester United, that didn't make him to request for a contract as long as Martial is requesting, he is on a year contract with additional year as extension while Martial wants a 3 years contract, he should be humble and understand this can't ce easily especially after his injuries record and poor performance, he ought to be humble,get a club and try to get his career back on track before requesting higher salary and longer contract