He was signed in 2014 as a young centre back with potential, and had a really good year in u23s, which led to him making his debut in the 1st team before the end of the season at left back. He did really well, looked fast and assured and solid defensively, but also covered ground going forward as well.
The next season, Baines was injured in preseason so he came in and started the season in the 1st team, again playing left back and did really well, before being dropped without really doing anything wrong when Baines returned, and found it hard to get back in. To my knowledge, he never got a try in the centre of what was an admittedly fragile defense under Martinez.
Tall and athletic, he always looked very composed to me for a young lad, and looked like we had a real find, but timing is everything and as the team struggled, he was never going to be dropped back in it.
After Martinez was sacked, in came Ronald Koeman, who basically washed his hands of anything that could be related back to Martinez. He was sent out on a terrible season long loan to West Brom under Tony Pulis, which was a complete disaster, and it appeared to destroy any confidence he had when he 1st came through. Another disaster of a season long loan to relegated Sunderland the following year, who signed both him and Tyias Browning on loan from us to replace half of their defence, and he was as good as done. Any leeway he might have had with Martinez was gone under Koeman, and even though Koeman was gone 18 months later, Galloway had dropped way down the pecking order and never looked like regaining his early promise.
Its a shame really, because early on, he looked like we might have another John Stones, but it wasn't to be.
Wish him luck at his new club and hope you have a good year. If he can rediscover what he showed in 2015, he could be a really good signing, but it's possible that his problems seem to be mental rather than physical, so it's a difficult 1 to judge.