How it happened
Heart of Midlothian won 5-0, a margin that the shot count and the expected-goals figures both back up. The home side led 2-0 at half-time and scored three more after the break without reply.
Mendy opened the scoring in the 20th minute. Calvin Miller doubled the lead from the penalty spot in the 32nd minute, and he scored a second penalty five minutes into the second half, in the 50th, to make it 3-0.
Cláudio Braga added a fourth in the 54th minute, which settled the contest with more than half an hour to play. Josh McPake completed the scoring in the 80th minute. St. Mirren did not score, and there were no red cards.
The numbers
Hearts took 18 shots, six of them on target. St. Mirren managed seven shots and one on target. Corners went 6-2 to the home side. Possession was almost even, with St. Mirren holding 51% to Hearts' 49%, so the gap came from what each side did with the ball rather than how long they kept it.
Expected goals finished at 3.44 for Hearts and 0.68 for St. Mirren. Hearts scored five from 3.44, so the result was a little more emphatic than the chances alone, though they were well ahead on chances too.
McPake, who played 82 minutes, had the best match rating on the pitch at 9.7, with one goal and one key pass from 51 touches. Braga and Miller each received a match rating of 8.3. Braga scored once and had one key pass. Miller scored twice, set up one goal and made two key passes in 56 minutes, and his expected goals total was 1.69.
What it means
Hearts are third in the Scottish Premiership with 16 points from eight matches, and a goal difference of plus 11. Their sequence reads draw, defeat, then three wins, and across their last 10 they have scored 23 goals.
St. Mirren are sixth with 10 points from eight. Their last 10 matches show four defeats followed by a draw and four wins, so this heavy loss interrupts a recent upturn.
Hearts have now won 22 of the 43 meetings between the clubs, with 11 draws and 10 St. Mirren wins. Their last win by a bigger margin than this one is not on record, but they also won 4-0 in October 2024.