A delighted Gray said: "It was fantastic for the boy. Scoring as early as he did helped give him the confidence to go on. The quality of his second goal was all about his movement in the box and taking the gamble.
"For his opening goal he needed a lucky ricochet for the ball to come back to him and we thought he was going to score with his first chance. But overall I was delighted with his movement and the good news about the month's loan is that there is no recall option."
Gray was less happy about his players' decision to allow Clarke to complete his hat-trick in the 69th minute after he had been fouled in the box by Crewe's goalscorer Colin Daniel. Clarke had been sent clear by a pass from Adebayo Akinfenwa and it was Northampton's top-scorer who would usually be taking the spot-kicks.
Gray said: "There is too much sentiment in the game in these situations and I would have preferred Bayo to have taken the penalty. I have seen games thrown away with decisions like that."