Second Division Rangers drew 1-1 against Peterborough on Friday, and Kerr was seen on his phone from just beside the dugout while casting his eye over the two number 10’s.
Gallen is eligible for the Irish panel through the grandparent rule, although he has represented England at U21 level. He is a former product of the QPR youth system, who spent eight years at Loftus Road before leaving the club in 2000 to join Huddersfield on a free transfer.
He then joined Barnsley a year later, but returned to Rangers’ in November 2001. Last season he earned rave reviews and claimed the club's Player of the Year crown after the campaign brought him 14 goals.
Platt also qualifies through grandparent, and the 6' 4" giant striker made the move to Peterborough United in January 2004 after his month-to-month contract at Notts County came to an end.
27-years-old in October this year, the former Rochdale front man started his career at Walsall after coming through the ranks.
Rangers' former Irish U21 International Martin Rowland's was not in action Friday.