The Honduran wideman was shunted out on loan in January after a disappointing first half of the season at Celtic, where he made just one league start all term.
But he’s not fared much better in Greece, where he’s started just two league games for Olympiacos, who were crowned Greek champions again this month.
He’s played just 18 minutes since the middle of last month and was an unused sub in their title-clinching win against AEK Athens last week.
And Spanish boss Mendilibar appears to have made up his mind about whether to exercise their £3.5 million buy clause to sign Palma permanently.
He said: “I have already made my decisions about the players who will stay and who will go at the end of the season.
“And it will be very difficult for them to change my mind in the remaining games of the season.”
Palma still has three years left of his deal at Parkhead.
