Walsall 3 (Cook 31, 90+4, Bradshaw 34)
Reds 1 (Nyatanga 29)
Barnsley could have had at least a point but shot themselves in the foot with another two quick-fire goals conceded after breaking the deadlock.
The Reds never got into second gear and were made to pay for some more sloppy defending.
It was a relatively slow start from both sides with a couple of pot-shots that sailed over from Berry for the Reds and Cook of Walsall.
Barely two minutes had passed when Berry tried his luck with ambitious volley that sailed well over and Walsall's effort came six minutes later.
Cook charged forward unchallenged and tried a lovely chip from 30 yards that wasn't too far over the bar.
Luke Berry took the Reds on the counter with a strong run down the Barnsley left. After squaring infield for Hourihane, the Irishman blazed his 25-yard strike well over the ball.
On 29 minutes the opening goal seemingly came from nowhere after the Reds forced a corner. Conor Hourihane sent in an out-swinger that Nyatanga rose highest to glance into the corner from 10 yards.
The lead didn't last much longer than a minute when another out-swinging corner, this time for the Saddlers, landed at the foot of Jordan Cook and his sweet half-volley sailed into the top corner from outside the area.
Bradshaw wasted a one-on-one with Turnbull as he blazed into the stand but after picking up possession a minute later, he twisted in the area before tucking into the bottom corner on 34 minutes.
The Reds were failing to replicate what Walsall seemed easily capable of - maintaining the pressure on their opponents in the final third.
The hosts went immediately on the attack after the restart and won a free-kick in a dangerous area, on the left-hand side of the area. Cook curled towards goal but his right-footed attempt grazed the roof of the net.
Barnsley got better as the second half progressed and Hourihane forced O'Donnell into a smart save at his near post after being found in the area by Cole on the hour. Moments later, Jennings drilled a low strike towards the far post and again O'Donnell had to deny the Reds a leveller.
Leroy Lita replaced Marcello Trotta for the Reds as Danny Wilson shook up the final third.
Barnsley had built up a little bit of momentum, but that was disrupted by an injury to Lewin Nyatanga but the defender was able to continue after receiving treatment on 69 minutes.
It was a memorable moment for 17-year-old Jack Cowgill as he came on for his debut with the injured Nyatanga making way on 79 minutes.
The Reds needed someone to step up to the plate and a free-kick 25 yards out seemed the perfect chance to rescue a point on 89 minutes. Hourihane stepped up but could only curl high over the bar.
In the fourth minute of five added on, Jordan Cook latched on to Masnet's lay-off and planted low into the corner. It was the simplest of goals as the Saddlers seemed to pass their way into the box from a corner.
Walsall: O'Donnell, Purkiss, Downing, A. Chambers, Bradshaw (Manset 87), Sawyers, Baxendale (Forde 68), Cain, J. Chambers, Cook, Henry.
Subs: O'Connor, Benning, Flanagan, Grimes, Forde, MacGillivray.
Reds: Turnbull, Brown, Berry, Hourihane, Abbott (Hemmings 77), Cranie, Jennings, Nyatanga (Cowgill 79), Cole, Holgate, Trotta (Lita 61).
Subs: Treacy, Digby, Boakye-Yiadom, Davies.
Referee: Trevor Kettle
Attendance: 4433 (503 Reds)