Alkmaar, Netherlands – Jozy Altidore scored a brace, but AZ 3, in the Dutch Eredivisie.
Altidore, a U.S. international, scored the opening goal in the 25th minute and gave AZ its second lead in the 58th minute with his ninth league goal and 13th in all competitions this season.
But Bas Dost scored his 20th Eredivisie-high 20th goal in the 77th and Luciano Narsingh put Heerenveen in front with just 9 minutes remaining in normal time.
Falkenburg bagged the equalizer 2 minutes later for AZ, which split the points and slipped two points off the pace of first-place PSV Eindhoven and down to third place.
AZ was even on points entering the day atop the table, but PSV beat Feyenoord, 3-2, to go clear atop the table, while Twente climbed into second place.
Dries Mertens scored his 16th of the season and Ola Toivonen his 13th for PSV, but the hosts needed Zakaria Labyad's goal 5 minutes from time for the win.
After Toivonen and Mertens handed PSV a two-goal lead, Guyon Fernandez notched a pair with goals in the 72nd and 79th for Feyenoord to temporarily level the score.
PSV won for the 10th time against just one draw in 11 home matches all season. Heerenveen slipped eight points off the pace in fifth.
AZ's result allowed Twente to climb into second place on goal differential, as Luuk de Jong scored his 19th goal of the season in a 1-0 win over Utrecht.
Siem De Jong scored a brace to help Ajax top Excelsior, 4-1, and remain within five points of PSV.