Rafa Benitez says Achraf Lazaar returned to Tyneside – after Newcastle United and Genoa ran out of time.
Lazaar's proposed loan move to the Serie A club broke down shortly before the Italian transfer window closed a week ago.
And the defender, signed from Palermo two years ago, was told to report back to Newcastle.
Lazaar – who has only made a handful of appearances for United – could yet leave before the end of the month.
Manager Benitez said: "Lazaar is still around because we didn't have time to do it with Genoa."
Meanwhile, midfielder Henri Saivet's loan move to Turkish club Bursaspor is expected to be completed in the coming days.
"Saivet's getting closer, but we have to make sure and wait for confirmation from Turkey that it will be done," said Benitez.
Saivet joined Newcastle from Bordeaux in January 2016.
The 27-year-old scored in last season's 3-2 win over West Ham United at the London Stadium.