# Sudoku, unclear next logical step?

Solved up until here, I took the sudoku through an online solver and it seemed to use a guess and check strategy? Is that the only way of getting the solution or am I missing something?

In the middle block, the base-middle cell is either $$2$$ or $$8$$, and the cell below is then $$8$$ or $$2$$, with the left-most cell on that row $$2$$ or $$8$$ again. Either way, the top-right cell of the left-middle block is either $$2$$ or $$8$$ (also due to the top-left block), and so cannot be a $$5$$, and also now the $$5$$ has only one place to go.