Morrow has had loan spells with Partick Thistle and Livingston over the last few years and also suffered cruciate ligament trouble. His scoring rate isn't that impressive (although I don't think he's played many gmaes) and he's not much different to Stewart Kean, so it's a strange one.
If message board rumours are to be believed, the pair are not the only trialists currently with the club. Apparently there are a few Scottish players and an American defender also training with the squad.
Meanwhile, the club have confirmed former Saint Allan Russell - another person taking part in pre-season training - is not on trial and won't be offered a deal.
Story source: The Belfast Telegraph, The Official St. Mirren Website