Welcome to the fifth edition of theScore's 2022-23 Norris Trophy Rankings and the fourth in-season version. New rankings are published once a month throughout the campaign.

These rankings focus on analytics and the all-around ability of defensemen rather than just points or reputation.

• xGF% = the share of expected goals a team produces while a player is on the ice at five-on-five

5. Miro Heiskanen, Stars

Previous rank: N/A

This list has a clear top four, but the No. 5 spot is wide-open. There's a case to be made for several blue-liners in this spot, though Heiskanen is far better defensively than offensive defensemen like Josh Morrissey, Roman Josi, and Dougie Hamilton while being much more of a threat offensively than shutdown defenders Jaccob Slavin and Jared Spurgeon.

Heiskanen is a versatile workhorse. He's effective at both ends of the ice at five-on-five, quarterbacks the Stars' seventh-ranked power play, and posted the lowest expected goals against per 60 minutes while shorthanded among Dallas' regular blue-liners on its second-ranked penalty kill. He's a jack of all trades.

4. Rasmus Dahlin, Sabres

Previous rank: 5th

Dahlin has been excellent since the last rankings, tallying 16 points in 14 games with a 52.97 xGF%. The main issue with his game this season continues to be a theme, though: He can't stay out of the box.

The young Swede has tallied 20 penalty minutes in his last 14 games and is up to 64 on the season - fourth-most among blue-liners. The amount of penalties he's taken has cost him more than a full goal on his 15.5 goals above replacement, which ranks third among defensemen.

There's nothing wrong with playing with an edge, but if Dahlin can harness his aggressiveness, he could easily climb higher on this list. Everything else about his game is there.

3. Adam Fox, Rangers

Previous rank: 2nd

Fox has been a staple of consistency, never ranking worse than No. 3 on our in-season Norris rankings. He's also never gone more than two consecutive games without a point.

The 24-year-old has driven offense at a high rate and been responsible defensively this season. Fox leads the Rangers' blue-liners in both expected goals for per 60 minutes and expected goals against per 60 at five-on-five. With Igor Shesterkin not reaching his usual lofty standards, Fox has undoubtedly been New York's MVP.

He falls one spot on this list through no fault of his own and was simply passed by a superstar who's starting to get red-hot.

2. Cale Makar, Avalanche

Previous rank: 4th

Fox and Makar are neck and neck, but the Avalanche phenom gets the edge because of the amazing job he's done carrying an injury-ravished team. With the roster around him now starting to get healthier, Makar has heated up further, recording 11 points in nine games with a 60.9 xGF% since the last rankings.

The torrid pace of late has pushed Makar, who leads all NHL skaters in average ice time, up two spots on this list. As things stand, it's not enough to move him into No. 1, but there's still plenty of time left for last year's Norris winner to make a push to repeat.

1. Erik Karlsson, Sharks

Previous rank: 1st

There's just no stopping Karlsson at this point. The two-time Norris winner has maintained his elite production, racking up 16 points in 13 games since the last rankings. His underlying numbers continue to improve, too, as he's posted a spectacular 62.84 xGF% in that span.

Karlsson isn't perfect defensively, but the way he's been able to drive offense at a historic rate on one of the worst teams in hockey remains remarkable and more than makes up for any deficiencies in his own end. His 51 even-strength points still lead all NHL skaters and are 19 more than the next highest defenseman. He also paces all blue-liners with 17.2 goals above replacement.

(Analytics sources: Evolving-Hockey, Natural Stat Trick)

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