The former Leeds player has evidently had his eye caught since returning to the club.
Paul Hart has only been back at Leeds United for a matter of weeks, but the new academy boss is already noting some exciting prospects for the future of the Yorkshire club.
The 62-year-old's position at Thorp Arch also sees him take the reigns of the club's development squad, of which he completed his third game in charge in a 3-3 draw against QPR yesterday.
"Frankie is a first year pro, he was a scholar last year," Hart said. "He's particularly impressed me with his fantastic ability; he can score, he can take people on, he drifts past people in a very smooth way.
"He's got a bit to do, but after three games: his attitude, what he's taken on board, he listens - it's very good to see him doing well."
Mulhern has been one of the sensations of the new campaign for the development team, and has been in scintillating form in front of goal for Paul Hart's side; scoring three goals already despite appearing just five times, some of which arrived from the bench.
With Leeds continuing to show an unwavering faith in their academy products - many of whom are excelling in the first team at present - it might not be long before the 18-year-old is given his chance to become the next star at Elland Road.