It was an early boost for the visitors who were supported by a large and noisy support who seemed to have infiltrated every part of the ground.
McTominay scooped a pass from Christie high over the bar in the 20th minute and three minutes later he bundled the ball in from close range after getting on the end of an inswinging John McGinn free-kick, but it was ruled out amid a VAR check and some confusion.
Scotland began to pose more of a threat, though.
Christie drove wide from the edge of the box and in the 37th minute McTominay took advantage of slack play by Jakub Kiwior and burst into the Poland box, but his cut-back evaded everyone in a dark blue shirt before Dykes slashed at a shot just six yards out to hit the side-netting.
However, the Scots were dealt another blow just before the interval when Anthony Ralston brought down Zalewski as the Pole drove into the box and Lewandowski sent Gunn the wrong way with an assured penalty.
The Scots were given early second-half hope when Poland failed to clear their lines and Gilmour stepped in to drive low past keeper Marcin Bulka with only his second-ever goal to get the Tartan Army singing again
The home side had more defending to do though as the Poles looked to restore their two-goal lead and Syzmasnki curled the ball just wide from the edge of the box.
There was little between the sides as the match entered the final 20 minutes.
In the 71st minute 28-year-old Ryan Gauld and 18-year-old Ben Doak came on to make their Scotland debuts along with fellow attacker Lawrence Shankland, with Dykes, McLean and Christie departing.
Doak made a quick impact on the right when he set up the over-lapping Ralston whose cut-back was confidently slid into the net by McTominay to make it 2-2.
That set up a frenetic finale where Hanley clumsily brought down Zalewski inside the box and the Pole got up and struck his penalty past the diving Gunn for a last-gasp winner.