Big substitute striker Chuks Aneke, on loan from Arsenal, was at the back post to head in a perfect cross from Mathias Pogba and deny Walsall all three points after four successive defeats in all competitions.
The hosts took the lead in the 12th minute when Byron Moore was caught in possession and Florent Cuvelier fed a superb throughball into the path of Jamie Paterson, who notched his third goal of the season with a well-placed effort.
Crewe fell further behind in the 26th minute, Adam Chambers finding Will Grigg who crossed low into the goalmouth where Cuvelier slammed the ball in from close range.
But the visitors began to create a few problems for the home defence and after Chambers fouled Moore, Luke Murphy bent a low free-kick into the goalmouth and defender Mark Ellis stabbed the ball over the line to raise the Railwaymen's hopes.
Crewe were denied what looked a certain penalty in the 82nd minute when Pogba was brought down by Andy Taylor, but Aneke's late leveller salvaged a point.