West Ham chief Karren Brady says sacked manager Slaven Bilic never recovered from the sale of Dimitri Payet.
Brady believes Bilic failed to handle Payet as the Frenchman pushed to join Olympique Marseille.
"In his first six months, when Dimitri Payet was inspiring the team with his Gallic brilliance, Bilic sometimes looked pensive, as though he thought this was a lucky break and might not go on," Brady told The Sun.
"He never quite recovered after the player staged a strike and went back to Marseille.
"He began to run out of ideas as the team's initial defiance to Payet's behaviour faded and less than a year later the manager had also departed."
Meanwhile, West Ham striker Javier Hernandez has been honoured with Mexico's 2017 National Sports Award.
The 29-year-old from Guadalajara received the distinction that every year recognises the effort and achievements obtained by Mexican athletes.
Chicharito was a key man for Mexico throughout the year, and was instrumental in booking their ticket to the 2018 FIFA World Cup in Russia by finishing first in the CONCACAF World Cup Qualifying section with 21 points.