Tom Pope scored his tenth goal of the season but most importantly the side kept a cleansheet as Vale made it four games unbeaten against their old foes.
Rob Page made three changes with Byron Moore, Ben Williamson and loanee Ryan Inniss all starting. Surprisingly, there was no place in the matchday squad for Achille Campion.
After a scrappy opening, it was Vale who opened the scoring when a good cross from Carl Dickinson fed Tom Pope who made no mistake to net his tenth of the season. Soon afterwards, Walsall dangerman Romaine Sawyers hit the post and the home side also had a good shout for a penalty turned down.
Chris Lines came on for Michael Brown during the break and Walsall immediately had a good chance but Neal remained alert. Vale countered with a chance for newboy Innis but the ref spotted a foul.
The Valiants brought on O’Sullivan to make his debut in place of Williamson and although the home side had further chances to equalise Vale’s new-look defence held firm.
Vale: Neal, Veseli, Inniss, Robertson, Dickinson, Moore, O’Connor, Brown (Lines), Marshall (Birchall), Pope, Williamson (O’Sullivan)
Subs: Johnson, Yates, McGivern, Luer