Having put the 23-year-old through an intensive training programme over the past two weeks, Grant believes he is now ready to be unleashed on a regular basis.
He told The News: "Quincy hadn't played for a long time, he didn't even train. In Russia the weather was minus 25, so he just couldn't.
"Since he came to Portsmouth, we've had a programme to get him to play again, to improve his fitness. Then when we changed the system to 4-3-3 in the second half against Southampton, it was a place for him to play and use his qualities.
"It's taken time but he's a talent. He's a good player. I think we will now see more of him. We need to use all our squad - our squad is short and not balanced. Quincy is very quick, can beat players one-on-one, he's good with the ball. You saw that with the goal he scored.
"I also like very much the crosses he can make. I know him from his time at Arsenal and followed him very closely when he was in Russian football. We know he's a player with a lot of quality."