AZ were knocked off their perch by Vitesse Arnhem on Saturday, but their hopes of going back up the ladder were boosted by Aron Johannsson's 18th-minute opener in Rotterdam.
However, two goals in three second-half minutes from Mitchell Te Vrede (48) and Lex Immers (51) turned the match in Feyenoord's favour, with Johansson securing a point for AZ from the penalty spot after 57 minutes.
The draw leaves AZ one point behind the leaders, while Ajax closed the gap on the top two to a single point with a 3-0 victory at NEC Nijmegen.
Frank De Boer's side had enjoyed a midweek Champions League win over Celtic and built on that on Sunday, with two goals from Siem De Jong (26 and 27) sandwiching Nicolai Boilesen's 29th-minute strike.
Defeat leaves NEC at the foot of the table with just one win from 13 attempts.
Quincy Promes rescued a 1-1 draw for FC Twente at PEC Zwolle which keeps the Enschede club in touch at the top.
Promes' goal arrived after 72 minutes to cancel out Guyon Fernandez's opener four minutes into the second half.
PSV Eindhoven's woes continued with a 2-1 defeat at NAC Breda.
The visitors led through a Jurgen Locadia goal a minute before the interval, but Kees Kwakman's second-half double inflicted a third loss in four matches on their opponents.
PSV lie eighth in the table, although just five points separate them from the summit.