Turkey need to improve their record in front of goal if they are to progress from World Cup qualifying Group D, in which they currently trail second-placed Hungary by four points.
Abdullah Avci's players did heed the call by building a 3-1 lead through Olcay Sahan, Selcuk Inan and Veysel Sari, with Edgars Gauracs notching Latvia's first, but Sabala took full advantage of a wobbly display from Turkish goalkeeper Mert Gunok to fire a decisive brace.
Seven minutes had elapsed when Caner Erkin picked out Sahan from the left wing and the Besiktas forward headed home at the near post. Turkey then doubled their lead in the 22nd minute when Inan found the bottom corner from the penalty spot.
Latvia opened their account through Gauracs, who pinged the ball past a hesitant Gunok from the edge of the box in the 53rd minute and, six minutes later, Sari's effort found the back of the net thanks to a sizeable deflection off Pavels Mihadjuks.
But Latvia were not yet ready to surrender and in the 68th minute Sabala took advantage of another moment of indecision from Gunok to cap a flowing team move with a composed finish.
Gunok was arguably to blame for Latvia's equaliser, too, as Sabala rose highest to head home a free-kick from deep to confirm Turkey's second-half implosion.