Lyle Taylor’s second-half strike condemned the Saddlers to a narrow defeat at AFC Wimbledon.
Jon Whitney’s side had the better chances in the opening period, with Jason McCarthy and Simeon Jackson each going close.
The Dons improved after the break and took the lead on 68 minutes when Taylor fired home at the second time of asking.
Tom Elliott could have extended the hosts’ lead but was twice thwarted by Neil Etheridge, while substitute Scott Laird rattled the bar late on.
Walsall were unchanged from the team that beat Peterborough 2-0 last weekend – the club’s fourth successive home win.
After a quiet start, the Saddlers threatened first on 15 minutes as Jason McCarthy cut inside onto his left foot and unleashed a fine curling strike which Dons keeper James Shea beated away.
Wimbledon grew into the contest and could have taken the lead when Andy Barcham’s fizzing left-wing cross narrowly evaded a stretching Tom Soares in the middle.
Chances were proving few and far between in a scrappy but competitive affair, although the Saddlers crafted a huge opportunity to take the lead seven minutes before the break.
Isaiah Osbourne’s inch-perfect through ball released Simeon Jackson in behind the home defence but, one-on-one with Shea, the Canada international lifted his right-footed effort over the bar.
Whitney’s men had the ball in the net on the stroke of half-time, Isaiah Osbourne bundling home from a corner, but the goal was disallowed for a foul on the keeper.
Half-time: AFC Wimbledon 0-0 Walsall
Neal Ardley’s Dons went close nine minutes into the second period, Dannie Bulman with a sweetly-struck 25-yard volley which a flying Neil Etheridge parried behind.
Jake Reeves was next to try his luck from range, but his attempt took a deflection and was comfortable for Etheridge.
Wimbledon were looking the more dangerous and took the lead on 68 minutes, Taylor firing low past Etheridge from 12 yards after the striker had initially missed his kick.
It was almost 2-0 moments later, but Etheridge produced an excellent finger-tip stop to keep out Tom Elliott’s glancing header from George Francomb’s right-wing corner.
Whitney responded by bringing on Amadou Bakayoko for Matt Preston and switching to a 4-4-2 diamond formation.
The change immediately gave the Saddlers more attacking impetus; Erhun Oztumer fired over from 25 yards before Kieron Morris arrowed a left-footed shot inches wide.
The hosts could have killed the game off with a minute of normal time remaining as Francomb cut the ball back to Elliott, but he steered his effort wide of the near post.
Walsall piled on the pressure in the closing stages and twice went close to an equaliser.
First, Shea denied James O’Connor from Oztumer’s corner before Laird crashed a venomous volley against the bar.
The Saddlers were almost caught on the break in added time, but Elliott’s fierce near-post strike was superbly kept out one-handed by Etheridge.
Full-time: Wimbledon 1-0 Walsall
Team: Etheridge, O’Connor, Preston (Bakayoko 73’), O’Connell, McCarthy, Chambers, Osbourne, Morris, Edwards (Laird 85’), Oztumer, Jackson.
Subs not used: MacGillivray, Dobson, Randall, Roberts, Moussa.
Attendance: 4,586 (613 Walsall supporters).