The 39-year-old Chelsea star made only his second appearance in 15 months when he replaced the injured Steve Simonsen on the hour. But his full length diving stop from Alex Nicholls' shot, which looked destined for the top corner, could be worth many thousands of pounds to cash strapped Stoke.
Mamady Sidibe should have given Stoke an eighth minute lead when he blazed high and wide from Paul Gallagher excellent through ball.
But most of the first half produced disappointing fair until City began to increase the tempo after the half hour. Luke Chadwick, Dave Brammer and Gallagher all had decent efforts before increasing pressure was rewarded just before the break.
Anthony Gerrard did well to block Karl Henry's 20-yard strike but the ball dropped invitingly to Sidibe, who lashed a left-foot shot into the roof of the net.
Walsall, cheered on by more than 3,000 fans who made the short trip up the M6, had threatened only once in the first period when Daniel Fox's deflected shot narrowly cleared the bar.
Stoke appeared to take a firm grip on the tie in the 49th minute when Gallagher fed Chadwick, who waltzed past Fox before curling a splendid left-foot shot beyond Andy Oakes from 18 yards.
But the visitors were right back in the hunt just two minutes later as Kevin James swept home from point-blank range after Mark Wright fired a low cross from the right.
Walsall almost levelled in the 69th minute when sub Nicholls benefitted from Michael Leary's clever step over to crack a shot against de Goey's left-hand post.
Stoke, who enjoyed the lion's share of the play, also squandered further chances to make the game safe before de Goey's heroics came to the rescue.