With the A-League season just over a week away, 23 year-old Watson joins the Reds as a short term replacement for Barbiero, who is recovering from an ankle injury.

A former member of the Qantas Young Socceroos (U-20s) and with previous stints at European clubs including Portuguese giants FC Porto, Watson provides the Reds with another midfield option.

Watson, the son of a former professional Scottish footballer, returned to Australia in 2007 and has spent this year playing with the Oakleigh Cannons in the Victorian Premier League.

Watson will be hoping to prove himself in his month long stint with the Reds if given the opportunity, starting with United's pre-season friendly against North Queensland Fury in Townsville on Friday night.

There will also be another new face on the trip north, with the Reds giving a trial to Bradley Norton, a 19 year-old left back from Victoria.