The Rise and Fall of Devils’ Jonas Siegenthaler

After New Jersey Devils general manager Tom Fitzgerald acquired defenseman Jonas Siegenthaler for a 2021 third-round pick, Siegenthaler has endured a rollercoaster-esque few seasons. When he first arrived in New Jersey, he was outright dominant in his own end, shutting down the opposition’s top offensive stars on a nightly basis. At times, he was the best defensive defenseman in the league. Now, it seems that his prior success was a flash in the pan – he’s become one of the league’s worst defensemen, period.

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Siegenthaler is now on injured reserve — he broke his foot blocking a shot in the second period of the Devils’ brutal loss against the Vancouver Canucks on Jan. 6. Perhaps the time away will give him the mental reset that he needs to channel the player he was in 2021-22. But, for now, here’s a look at his journey from being traded to the Devils to this season:

Devils Acquire Siegenthaler From Washington

On April 11, 2021, Fitzgerald sent a 2021 third-round pick to the Washington Capitals for Siegenthaler. At the time, the 23-year-old was being used as the Capitals’ eighth defenseman. He scarcely saw ice time — in fact, he hadn’t played more than 28 seconds total since February of that year — and many thought he would benefit from a change in scenery.

After the trade, head coach Lindy Ruff touted Siegenthaler as a solid-bodied, stay-at-home defenseman who would help the Devils on the penalty kill while being a complementary partner for one of the team’s more offensive-minded blueliners.

Jonas Siegenthaler Washington Capitals
Jonas Siegenthaler, Washington Capitals (Amy Irvin / The Hockey Writers)

His first two seasons in Washington should be considered a success by any measure — he was always one of their better defensemen in expected goals against per 60 minutes (xGA/60) and had a positive expected goals share (xGF%) in each season, most notably an astounding 57.13% xGF% in his rookie campaign. Siegenthaler found similar success in his eight-game stint with New Jersey in 2020-21, posting a xGF% of 55.51% while leading the team in xGA/60 (1.89). At the time, it looked like Fitzgerald made a steal of a trade.

Siegenthaler’s 2021-22 Dominance

His eight games in 2020-21 were just a taste of what was to come in the following season. Whereas, in those few games, he played a more sheltered, bottom-four role, Siegenthaler impressed so much (in that small sample and the preseason) that he entered the 2021-22 lineup in a top-pairing role, playing alongside two-way stud Damon Severson for most of the season, logging 620 of his 1220 5v5 minutes with him. For comparison, Siegenthaler put in 270 minutes with his second-most common partner, PK Subban.

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That season, Siegenthaler was one of the most dominant defensive defensemen in the NHL. His 5v5 xGA/60 of 2.2 was tied for 7th in the league, and he led all skaters in defensive goals above replacement (GAR) by a healthy margin while placing 7th among defensemen in shorthanded defensive GAR. He did this while consistently playing against the opposition’s best players, completely shutting down the Connor McDavids and Nathan MacKinnons of the league every game. His offensive impact wasn’t perfect, but he still ended the season with a more-than-respectable 52.51% xGF%.

Siegenthaler Falls Off Defensively In 2022-23

In the 2021 offseason, the Devils signed star offensive defenseman Dougie Hamilton to a massive seven-year, $9 million AAV contract. As a strictly offense-oriented rearguard, Hamilton naturally required a bit of stability next to him. In 2021-22, that stability was provided by Ryan Graves, but the duo didn’t find much success together. Enter Siegenthaler, who began and ended the season as Hamilton’s defense partner.

Dougie Hamilton, New Jersey Devils
Dougie Hamilton, New Jersey Devils (Jess Starr/The Hockey Writers)

Hamilton seemed to unlocked the more offensive side of Siegenthaler in 2022-23, as his offensive metrics skyrocketed — Siegenthaler had never posted an expected goals for per-60 (xGF/60) of more than 2.45 until he catapulted to 2.87 alongside Hamilton. Presumably, as a result of playing alongside such a heavily offense-oriented blueliner, the defensive metrics began to skid a bit, dropping his xGA/60 from 2.2 in 2021-22 to 2.38.

This version of Siegenthaler was likely the best we saw in a Devils uniform, as both his offensive and defensive expected goal rates were very, very good, resulting in a xGF% of 54.70% in the 80 games he played. Still, the defensive drop-off was a red flag for what was to come in the 2023-24 season.

Siegenthaler’s Disastrous 2023-24 Season

After Siegenthaler and Hamilton’s success together in 2022-23, they were reunited as the Devils’ top pairing again this season. After all, if it ain’t broke, don’t fix it, right?

Unfortunately, their success seemed to be a one-season affair. The offensive numbers were there — Hamilton’s offensive rates were among the league leaders — but their play in their own end was abysmal enough for it not to matter. Their xGF/60 continued to rise to 3.5, but their xGA/60 continued to rise also, to 2.63. In a season when the Devils’ goaltending has been their Achilles’ heel, the defensive work from seasons past needed to be there so that Siegenthaler could compensate for the suspect-at-best play in net. Because it fell off, the pairing was outscored 11-10 despite whatever story the underlying numbers told.

Jonas Siegenthaler New Jersey Devils
Jonas Siegenthaler Microstats for the 2023-24 Season (Corey Sznajder, AllThreeZones)

The above player card, courtesy of Corey Sznajder of AllThreeZones, shows Siegenthaler’s horrendous defensive microstats for this season. The offensive numbers are somewhat irrelevant simply because of the type of player he is, but the defensive stats are shockingly bad. The zone entry defense is acceptable — he’s solid at denying entry to opposing players — but the real issue is in trying to clear the puck. He’s been more or less incapable of getting the puck out of the defensive zone, meaning that the opposition can keep up the pressure quasi-indefinitely. It’s a real problem, and it has caused most of his defensive struggles this season.

Devils Outlook Moving Forward

Depending on the severity of the break, Siegenthaler could find himself out of commission until anywhere between mid-February and early April. It might be a blessing in disguise, as his 2023-24 season has been catastrophically bad — a mental reset, along with the physical rest, will probably end up doing him some justice. Pair that with the likelihood of the Devils acquiring another defenseman, which could force Siegenthaler to play in a more sheltered role, might also contribute to more success for him once he returns.