Beni Baningime could make his debut against Celtic on Saturday after joining Hearts from Everton on a three-year deal.
The 22-year-old midfielder featured 12 times for the Premier League side and was with Derby County last term.
He trained with Hearts for the first time on Thursday and is in line to play in the Scottish Premiership opener.
"He brings energy, work ethic, moves the ball quickly," said Hearts manager Robbie Neilson.
"He will be in the squad, it's just whether he starts."
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