Pool opened strongly, forcing the Tykes onto the back foot early on with midfielder Gary Taylor-Fletcher causing trouble down the flanks.
His neat footwork freed Stephen McPhee inside the box only for the frontman to scuff his effort wide.
Just minutes later it was again the wing play that caused problems from the home side when Stephen Crainey provided a pinpoint cross from deep to pick out Taylor-Fletcher and his well-controlled looping header left Luke Steele no hope for the opener.
Pool continued to press and with a barrage of chances had Barnsley firmly on the back foot for long spells of the half.
Five minutes before half time the Tykes finally began to find their way with Jamal Campbell-Ryce powering down the left past a beaten Shaun Barker, but his curling effort whistled wide of the post.
The South Yorkshire side were back on level terms on the stroke of half-time when Jon Macken pulled back a perfectly weighted ball from the far post and Campbell-Ryce had little to do as he side-footed past the helpless Paul Rachubka.
After the break Pool continued to play the dominant football and forced the lion's share of the chances.
The best of these came just three minutes after the restart as Andy Morrell found space behind a stretched backline.
Steele's good body save rebounded off the fortunate Steve Foster, but the post came to the rescue for the visitors.