From my side: The Leafs only have a single top-pairing D on the team.....Rielly, who is a #2, young, and getting better every year.
Gardiner, to me, is closer to a #3 at best. Really more of a #average-low end #3/#4. Just way too inconsistent and when he's off, he'll look out of sorts completely. He has long spells of playing like a #1/#2 but they are too far inconsistent to ever designate him with a higher grade, given his small sample size poor-spells can be absolutely horrific.
Zaits is a #4 to me. Zaits might have a bit more to give upside wise. Though I think Rielly-Hainsey in general, have been very good this year for the most part- the problem is they play only about ~1/3 of the game. To be frank, Hainsey hasn't looked out of place as a #2 defensive D next to Rielly almost all year.....he's been our best defensive d-men while Rielly's probably been our best overall. It's tough for me to give him a appropriate designation but Hainsey is closer to a #3 than a #4, IMO. People give him a hard time but don't acknowledge he's been a top 4 D for a large majority of the last decade or so, and has had some of the toughest usage of any D in the league while at it.
As per our bottom pairing- Borgman (right now) and Polak (definitely) are not NHL caliber players. A myriad of problems defensively and it's mostly personnel.
With those designations, your looking at a below average->bad defense in this league. 3 guys that are second pairing defenders at best. A bottom pairing that is probably close to league worst.
Inherently, not much way to upgrade team defense through avenues other than drafting/development, perhaps UFA (not for at least 2 years), and trade (very unlikely that a #1D ever hits market....anything short of it isn't really a true upgrade).
I do think upgrading/moving furniture with our forwards, and perhaps getting a more competitive and physical #3C could have a more profound effect on team defense than actually upgrading the bottom 4 in itself.
If I had to rank the issues defensively:
1) Forward group- Bozak..........then JVR. I'd include Martin there but I can accept he fits a niche role. Can't shelter a line driven by Bozak, it's going to be horrible in its own end/driving play/possession the other way no matter the reshuffling of applicable wingers + usage. Just think Bozak provides nothing defensively, minimal offensively besides rare spurts of creativity at ES and a whole lot of negatives- possession, zone time, sustained pressure going the other way, and a ton of loose pucks/battles lost or conceded.
Just think in a game that's heavily fueled by momentum and pace, his negatives far, far outweigh the positives....and we've already provided him as much as we can realistically from a usage standpoint.
That's essentially one line that will be horrible regardless of usage. If the Kadri or Matthews line are off, there's very little margin of error.
2) Bottom pairing- Polak and Borgman aren't NHL caliber. Carrick is a #5/#6D that requires favourable usage and doesn't have the proper partner- given his issue is size, physicality and our team weakness fits the same narrative.
Perhaps we have the internal upgrade already with Dermott, who's a lot better than Borgman/Rosen, from what I've seen, IMO.
3) Top 4.....specifically Gardiner's having a pretty big bad spell right now. We see this every year with him, if the trend follows....his play will pick up as the year goes on. Problem is, if your not consistent in this league or have the compete/will to battle through it.....your an expendable talent in this league. You have replaceable level talent like Del Zotto (which I would never endorse the Leafs to get) that can steal your job in this league.
