Josh Kay has started twice for Town now since moving to the Proact from Championship club Barnsley.
The attacking midfielder suffered a disappointing debut, losing 4-0 at Accrington Stanley.
But on Saturday he played a full part in the 2-0 victory over league leaders Luton Town.
Kay was involved in the move that led to the first goal and provided pace and energy in the middle of the park.
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Lester can’t wait to see the 21-year-old get up to full speed.
“When Josh Kay gets into our tempo of play he’ll become something different,” said the manager.
“He’s top drawer, I’m excited about him.
“He’s a young lad, he didn’t come through academy systems, he’s not had long in the game, he’s showing bits of real flair and he can run.”
Pace is something Chesterfield have been lacking this season and Kay’s ability to break and move play up the pitch quickly excites Lester.
It helped Town turn defence into attack on a number of occasions on Saturday, stopping Luton from building up any real momentum.
The Spireites gaffer thinks Kay’s speed and attacking threat will endear the youngster to those in the Proact stands as well.
“When he opens his legs up and breaks from midfield people can’t catch him, he’s too quick,” said Lester.
“He’s got two feet, left and right, he’s going to bring us goals.
“I think the fans are going to love him here.”
Kay began his career with AFC Fylde before a move to Oakwell.
He went back to the Coasters on loan and also spent time with Tranmere before sealing a permanent move to the Proact.