The game started quietly with few openings, with Martin Woods's 30-yard drive sailing over the bar for the only sight of goal of the first 15 minutes.
Lee Novak fired inches wide from a loose ball and then slid over from seven yards out as the away side increased the pressure, but neither side could find a breakthrough before half time.
However, it took only five minutes after the restart for the deadlock to be broken as Ebanks-Blake received Jay O'Shea's pass, cut inside and placed a shot past the unsighted Jayson Leutwiler to give the Spireites the lead.
The Shrews responded with a double substitution and a period of pressure on the ball, but Dan Gardner nearly made it two for the away side when he hit the underside of the crossbar with just Leutwiler to beat.
The home side were punished for their flat display shortly after the hour mark when Chesterfield did double their lead, Sam Morsy breaking from midfield before exchanging passes with Novak and firing home.
Shrewsbury finally got going in the last 20 minutes and were rewarded for their belated endeavour when Mat Sadler curled in a superb strike with two minutes of normal time to play, but it was too little, too late for Micky Mellon's side.