Grainger has played in Saints' last two friendlies as a trialist and has done well. His talent what was in question, the games more being used to measure his fitness after he suffered a serious injury while playing for Hearts last season, which ruled him out for nine months.
Grainger turns 28 tomorrow and has been handed an early birthday present with a one year Saints contract, which has the option for an additional season. The former Gretna, St Johnstone and Dundee United man - who won the Scottish Cup with Hearts last year - was a wanted man with Carlisle supposedly interested, while he'd also trained with Blackpool and Sheffield United during the summer.
Grainger is unquestionably a good player, the main concern is his fitness and whether he has any more injury problems. If he doesn't then he will prove a fantastic signing.
Grainger wasn't signed before yesterday's game with Stockport so featured as a trialist, as did Richardson. The midfielder, who has been loaned out by Newcastle a few times in recent seasons, did well and could join Saints on loan for the coming season as a replacement for his United team mate Conor Newton.
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Source: Mirren MAD