Sweden produced several dangerous chances in the first half, but had to go into the half-time break with a 0-0 scoreline after Sweden - and Stina Blackstenius - had another goal disallowed for offside.
In the 25th minute, she placed the ball in the net after a run and it was with the smallest possible margin that the goal was ruled out.
It was a hungry blue-yellow national team that regained the field after the break.
Fridolina Rolfö immediately got the chance, but had to see her dangerous finish saved and even though Sweden was the team that led the game, the attacks were fruitless when the passing game didn't quite go right.
Kosovare Asllani, clearly marked by the Belgian defence, received a nasty stamp with just over 25 minutes left of regular time, but continued to play.
Sembrant match winner
With barely 20 minutes remaining, Sweden had worked together 26 goal chances and six shots on goal - but no note in the minutes.
The Swedish corners also lined up and the eleventh, after 77 minutes, was just like the previous ones without result.
Sweden continued to challenge but when normal time passed it was still goalless.
But with 90 seconds left in added time, Sembrant, after the 13th corner, was finally able to score the decisive goal and avoid extra time.
In the semi-finals, which will be played already on Tuesday, England awaits.