The Mexico international struggled for playing time at Old Trafford last season and has aired his frustration at being continually overlooked for a starting berth.
Hernandez struggled to nail down a starting spot at Old Trafford in 2013-14, with Wayne Rooney and Robin van Persie firmly entrenched at the top of Moyes' pecking order before the Scot's sacking in April.
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"This whole year has been very tough. Players need confidence more than anything else and I've been very short of it," he told the press. "Very few people have shown faith in me over this past year."
New Manchester United boss Louis van Gaal is plotting an overhaul of the current squad and it is unclear whether the Dutchman will choose to cash in on the 26-year-old, with several clubs reportedly interested in the striker.