Hugo Sanchez has launched a scathing attack on the Manchester United manager in the wake of Chicharito's last gasp move to Bayer Leverkusen.
Chicharito ended his five-year association with the Red Devils earlier this week after sealing a £7.3 million move to Bundesliga side Bayer Leverkusen.
Prior to completing the move, however, Hernandez had featured for Manchester United in their Champions League qualifier against Club Brugge.
Though United won the game comfortably, the Mexican was guilty of missing several chances with the most notable being a penalty.
Hernandez put the spot kick wide after slipping during his run up in a move that prompted something of an outpouring on social media.
The most notable clip doing the rounds featured Van Gaal's reaction to the Mexican's miss, with the Dutchman's look of disgust proving popular with fans online.
However, speaking to Spanish publication Marca, Sanchez slammed the United boss as “a wretch” for failing to keep faith with Hernandez after what he described as a “bad day at the office”.
“I hope this reverberates around England and people realise that he's a bad person because of the way he treats his players,” he said.
“He has to be professional. You have to treat players like human beings.”
Hernandez scored 59 goals in 157 games for Manchester United, following his arrival from Guadalajara in July 2010 with the 2012-13 campaign proving his most prolific in front of goal after 18 goals in 36 games.