How the Maple Leafs defense fared in Morgan Rielly's absence

Morgan Rielly suffered a significant knee injury on Nov. 21 and it appeared to spell impending doom for the Toronto Maple Leafs. Already missing Jake Muzzin due to another head/neck injury suffered in October, there were major doubts about how the Maple Leafs would remain afloat in the vaunted Atlantic Division, while missing the two central tenets to their blue line.

One month can make all the difference in the world. Entering the new year, Toronto sits second in the Atlantic with an impressive 22-7-6 record, the third-best mark in the NHL, and the franchise is finding ways to win games in a multitude of ways. It once appeared that a trade for Jakob Chychrun was the only solution to their bandaged corps, but Toronto’s defensive group has shown rapid internal improvement.

Rielly and Rasmus Sandin are both listed as day-to-day and the former is expected to return to action on Thursday against the Arizona Coyotes, so it’s worth examining how the Maple Leafs’ defense weathered the storm against a rash of untimely injuries.

Mark Giordano has allowed Justin Holl to play best hockey of his career

Mark Giordano is playing on the most team-friendly contract in the NHL and his contributions to the Maple Leafs extends far beyond his on-ice impact. We can start with assessing how he’s played this year as the 39-year-old has been outstanding for the Maple Leafs, and has allowed his primary partner, Justin Holl, to not only crawl out of an early-season hole, but become a genuine asset to this year’s squad.

Giordano has primarily started his shifts in the neutral zone, or on defensive zone faceoffs, but sports a 52 percent Corsi and a 57.7 percent share of the expected goals at 5-on-5 via Natural Stat Trick. He’s meaningfully creating secondary offense and alleviating high-pressure situations in his own end, while operating as a mentor to Holl, along with the Maple Leafs’ emerging talents in Rasmus Sandin and Timothy Liljegren. Giordano also ranks 17th in the NHL with 69 blocked shots in all situations. The 39-year-old is throwing his body around, he’s logging heavy minutes against top-caliber pairings and his underlying numbers paint the picture of his best season since he won the Norris Trophy in 2019.

Giordano and Holl have logged 277:26 together at 5-on-5 and been on the ice for 10 goals with six against, while hovering just under a 55 expected goals share. They are Toronto’s most-used pairing 35 games into the season and even with Rielly and Sandin expected to return to the lineup, this is a duo that ought to remain intact — although, you have to expect Giordano’s workload to decrease when Rielly and Sandin return. He may be balling out, but the Maple Leafs have to make sure he has enough in the tank come April.

Holl struggled badly out of the gate and boy, did Maple Leafs fans make him listen to their discontent. He was booed at Scotiabank Arena during the early stretches of November, but Giordano has brought out the best of his game. Holl is a player who is prone to freelancing and entering the rush, while Giordano is innately aware of where his partner is at all times, allowing the 30-year-old to play to his strengths without overthinking. In many ways, Giordano operates as the ultimate safety valve — both Holl and Liljegren have shown notable improvement and sounder decision-making with respect to zone exits when paired with the seemingly ageless veteran.

“We can’t talk about Giordano without talking about Justin Holl. Justin Holl has been fantastic down this stretch,” Keefe told reporters on Dec. 8.

Holl is averaging 21:25 of ice-time per game — he’s played as many as 26 minutes in a single game — and though he’s been prone to some inexcusable turnovers in the past, he’s quietly playing some of the best hockey of his career after Rielly’s injury. Maybe Holl’s uptick in form won’t last forever, but he’s certainly owed some apologies from the most vocal part of the fan base.

The internal development of Sandin and Liljegren

Although this is a Maple Leafs team firmly focused on the present, you have to be mindful of the internal development of their young players who’ve yet to hit their prime. Sandin and Liljegren are both first-round picks and their continued success at the NHL level would help fend off the concern the Maple Leafs haven’t graduated their prospects at an acceptable rate.

Sandin was playing the best hockey of his young career and earned trust in all situations from Keefe over the past month, before suffering a neck injury on Dec. 20 against the Tampa Bay Lightning. He was allowed to operate as the lone defenseman on the power play when the Maple Leafs were beginning to test out their five-forward formation.

“I think you can tell the fact that he’s played more, he’s in more of a groove and the injuries, you have less options so you just put him out there," Keefe said of Sandin on Dec. 10. "And he’s growing on the fly. He’s figuring things out. He’s being relied upon, I think he’s done a nice job.

“Everybody thinks playing the power play is great and easy and all that. It’s not easy, it’s a challenge. It’s a stressful situation to make those decisions and make those plays and execute at a high level at key times. I think those experiences are helping him grow and there’s no doubt that he’s found a different level in his game here versus where he was at earlier in the season, not unlike a lot of our team that has really turned the corner in the last month.”

Sandin is developing as a power-play quarterback and is rapidly improving at getting his shots through traffic. And though he’s undersized, the game appears to be slowing down for Sandin, so he’s able to make clean zone exits routinely. These types of plays don’t show up on highlight reels, but Sandin is showing confidence and decision-making that belies his 22 years.

The Athletic’s Dom Luszczyszyn projected Sandin to be providing $7.7 million in surplus value on his contract on Dec. 22, while ranking in the 90th percentile of defensive defenseman.

"I think you learn a lot about their character," Keefe said of the pairing following a 4-0 win against the Dallas Stars on Dec. 7. "The team needs them to step up in a big way, and they've done exactly that. Like, those guys played hard today. They played a lot of minutes tired, too."

Liljegren needed some time to work his way back into the lineup after missing training camp with a hernia. He hasn’t played at the breakout level Sandin has, and he’s still prone to more mistakes in his own end. It hasn’t been all bad, however. Liljegren’s plus-skating stands out in the NHL, as he's able to skate his way into clean zone exits, and he’s benefiting from the continuity alongside Sandin. Sandin’s all-around excellence — in a similar but inexact comparison to Giordano — has allowed Liljegren to play with full confidence and shut down opponents by using his speed, forcing them to outside shooting lanes.

It’s been important for the Maple Leafs to remain flexible for the future. Sandin looks like a breakout star while Liljegren is coming into his own as an NHL-caliber defensemen. They are some of the few players on the Maple Leafs yet to hit their prime and have shown notable improvement this year. Liljegren may end up with a promotion of sorts, as a result.

What’s next for Rielly and Sandin?

I originally thought Rielly would be paired with TJ Brodie upon returning to the lineup, but Keefe appears to have other ideas. Rielly returned to practice Wednesday, paired with Liljegren, while Sandin was paired alongside Jordie Benn.

So what does this mean for the Maple Leafs going forward?

Rielly will return Thursday against Arizona alongside Liljegren and we’ll see how long this pairing lasts. Although Rielly is capable of playing at an All-Star level, it’s unfair to expect this type of production right away and there are stylistic concerns, too. Rielly and Liljegren are both offense-minded defensemen prone to significant defensive lapses, so it may make sense at some point to return them to Brodie and Sandin, respectively.

Giordano-Holl won’t be broken up. So who will be the odd man out?

Although Sandin practiced alongside him on Wednesday, it appears that Benn might have to head to the press box when Rielly returns. Conor Timmins won unsolicited praise from Keefe on Dec. 20 and he’s 24, providing much more upside than the journeyman. This isn’t to say that Benn won’t ever see the ice again, only that if it becomes a question of running seven defenseman, he’ll be the odd man out. Benn was the worst Leafs defender against the Blues on Wednesday and if recency bias plays any factor, he’ll have to wait his turn again.

Toronto withstood a rash of injuries to its defensive corps and somehow looked stronger than ever during Keefe’s tenure with the club. It ought to provide confidence for a group that is rolling through the regular season, with much larger goals on the horizon.

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