Jack Lester kept Sheffield United's play-off dream alive scoring a second-half penalty that dealt Walsall's survival hopes a severe blow.
Lester won the spot-kick shortly after the break following an Ian Roper foul.
He dusted himself down to rifle home the winner, his 15th goal of the season stopping a sequence of four United defeats in five matches.
Walsall were unable to get back on level terms despite good efforts from Lee Bradbury and Matt Fryatt.
The star performer in a stop-start match was Blades midfielder Michael Tonge who carved out the game's first two chances with trademark long-range efforts that flew over the crossbar.
On-loan Jermaine McSporran responded for the Saddlers with a wayward drive in the 18th minute but the opening quarter was a messy affair with neither side
mustering a clear-cut chance on goal.
United boss Neil Warnock has bemoaned his side's lack of creativity and that
was in evidence again as the visitors floundered on the edge of the Walsall
penalty area.
In-form Andy Gray was first to test either keeper, his header from Rob
Kozluk's cross bringing the best out of Walsall's James Walker.
Tonge then forced Walker into two fine saves with long-range shots.
United made the all-important breakthrough three minutes after the interval
when Roper brought down Lester in the penalty area and referee Mark Clattenburg did not hesitate in pointing to the spot.
Lester's goal prompted Walsall player-manager Paul Merson to bring on Lee Bradbury as the hosts seached for an equaliser.
After Bradbury headed over Matt Fryatt launched a stunning right-foot volley that Paddy Kenny tipped over before Bradbury again went close with a drilled effort.
Merson then provided the cross for another Bradbury header that flashed wide
and McLeod's right-foot 25-yarder whistled over the crossbar as the game opened up.
But Warnock decided to shore up his midfield for the closing stages, sending on
Mark Rankine for Lester, and help United's cause in closing out the match.
Walsall: Walker, Bazeley, Roper, Ritchie, Kris Taylor, Osborn, Emblen, Andrews, Merson, Fryatt, McSporran. Subs: Kerr, Corica, Wrack, Wright, Bradbury.
Sheff Utd: Kenny, Kozluk, Page, Morgan, Wright, Phil Jagielka, McCall, Tonge, Gray, Lester, Allison. Subs: McLeod, Forte, Shaw, Rankine, Montgomery.
Referee: M Clattenburg (Co Durham)