Rayo Vallecano boss Paco Jemez has claimed that he could quit his position at the Spanish club less than one month before the start of the new season.
Jemez has been widely lauded for his work on a tight budget at the Madrid club and has been linked with a move away this summer.
It had been thought that Rayo had persuaded Jemez to stay after offering a new deal, but the Spaniard has said that he might consider his position following Saturday's 5-0 friendly defeat to Segunda side Albacete.
"[The team were] shameful and horrible, just horrible. Many players have wasted a very good opportunity to earn a place in the team," he told reporters.
"We must strengthen in all departments, budget permitting. We must draw conclusions [from this result] and, maybe, it's time to change the coach."
Rayo have already signed six new players this summer.
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