OPA output inversion during input overdrive

Bell,

Below please see a simplified op amp schematic of OPA234. The reason behind a phase inversion has to do with the fact that in a normal operation emitter, Ve, follows the input, Vin, but collector of the input transistor, Vc, should be always 180 deg out of phase with the input - this is only possible when Vce>Vsat.  As the input Vin+ is pulled down, Vc goes up and output goes down - as you would expect (see schematic on the left).  However, when you overdrive the input below a negative rail, the voltage between a collector and emitter get smaller to the point that Vce=Vsat and Vc cannot move up (out of phase) with the input and thus gets dragged down causing the phase inversion you see on the schematic on the right below.

Tina simulation model uses greatly simplified circuit and is meant to show only linear operation of OPA234.