The biggest problem in Toronto this season has been identified and it's not even the goaltending

Comparing the 2022-23 Maple Leafs to current rendition of the club, there is a stark difference in defensive stats - and I'd even go so far as to say the numbers from last year to this year are alarmingly different.

In 2022-23 the Maple Leafs were:

7th in goals against per game
10th in expected goals against per game
13th in shots attempts against per game
8th in scoring chances against per game
15th in slot shots against per game
15th in rush shots against per game
7th in odd-man rushes against per game
10th in zone denial success rate.

Comparatively, the 2023-24 Maple Leafs are:

26th in goals against per game
20th in expected goals against per game
29th in shot attempts against per game
23rd in scoring chances against per game
28th in slot shots against per game
29th in rush shots against per game
25th in odd-man rushes against per game
26th in zone denial success rate.

You could make the argument that injuries have hampered the Leafs back-end this season but the same argument can be applied for the 2022-23 season and at times it might have even been worse off last year.

As far as who left the team last summer, the Leafs did lose Justin Holl, who was a big part of the D corps last season, and they also lost deadline additions Luke Schenn and Erik Gustafsson. The Leafs also had Rasmus Sandin for much of the year, though the defensive side of the game was never really his strong suit - especially in his own end.

The Leafs, with Mike van Ryn running the defense, are essentially in the bottom-third of every category after the Maple Leafs were in top-half last year. Goals against per game can be attributed to Ilya Samsonov's nightmarish season but shot attempts per game, rush shots against per game, and zone denial success rate are the categories that stand out the most and are entirely pinned on the defensive schemes and players involved.

For the Maple Leafs to contend this season, let alone push for a longer playoff run, the defense needs to shape up and at the very least enter the middle of the pack rather than languishing near or at the bottom of the league. These are not Cup contending numbers - not by a long shot.