A lot has gone right for the New Jersey Devils to begin the 2024-25 season. One of the biggest developments through 21 mostly successful games is a largely elite defense.

According to TopDownHockey, the Devils are allowing the third-fewest expected goals against per 60 minutes (xGA/60) in the league at five-on-five. Additionally, they have one of the better penalty kills in the league, succeeding at a 84.5% rate (seventh-best in the league). A large reason for all this defensive success has been the resurgence of defenseman Jonas Siegentahler.

Surprising Struggles of 2023-24

Last season, Siegenthaler had the worst season of his career. His -10.9 goals above replacement (GAR) and -6.3 expected GAR (xGAR) were both by far the worst marks of his seven-year NHL career.

Not only were these marks the worst of his career, but when it was all said and done, he graded out as one of the worst defenseman in the league. His on-ice offensive metrics ranked in the league’s first percentile while his on-ice defensive metrics ranked in the 10th percentile. Overall, his GAR and xGAR ranked 309th and 300th, among 310 defensemen, respectively.

This all was a very confusing development given since coming over from Washington, Siegenthaler had emerged as one of the better defensive defensemen in the league. In 2021-22 and 2022-23, Siegenthaler’s defensive on-ice metrics ranked in the league’s 99th percentile and 71st percentile, respectively. Then, in 2023-24, that figure plummeted to the 10th percentile.

Coming off a career-worst season, which was far from his norm since coming to New Jersey, a lot of eyes were on the 27-year-old. Not only did he sign a five-year extension worth $17 million, but the Devils all of a sudden found themselves with tons of depth when it came to defensive prospect. So far, he has responded in a big way.

Bouncing Back In a Big Way

As mentioned, the Devils strong defensive play is because Siegenthaler is resembling more of his 2021-through-2023 form. Through 21 games, his on-ice defensive metrics are back in the 99th percentile. Specifically, his defensive xGAR and GAR both rank second among 239 defensemen this year, trailing only teammate Johnathan Kovacevic.

Further evidence of just how strong Siegenthaler has been defensively is among 149 defensemen who have played at least 200 minutes of five-on-five ice time, he ranks sixth or better in xGA/60, scoring chances against per 60 (SCA/60), and high-danger attempts against per 60 (HDCA/60). When Siegenthaler is on the ice, the opposition is getting nothing in terms of quantity or quality.

The success extends beyond just five-on-five as well. He ranks fourth in Corsi against per 60 (CA/60) and fourth in shots against per 60 (SA/60) while on the penalty kill (among 156 defenders to play at last 10 minutes of penalty kill time). The above chart further describes his penalty-killing success (“SH Defense” section). Not only is he elite at defending at even strength, he is also one of the better penalty killers.

Dynamic Duo

Only one pairing in the league has played more at five-on-five than the one Siegenthaler has been assigned to by head coach Sheldon Keefe. Siegenthaler, along with offseason acquisition Johnathan Kovacevic, has played over 300 minutes of five-on-five ice time. In doing so, they have emerged as the best defensive pairing in the league.

The duo is allowing the eighth-fewest xGA/60 of 110 defensive pairings to play at least 75 minutes of five-on-five ice time. As mentioned above, the duo also ranks No. 1 and No. 2 in both defensive GAR and xGAR among 310 defensemen in the league.

Kovacevic was acquired by general manager Tom Fitzgerald in the offseason for a fourth-round draft pick which looks like a steal. Prior to this season, the 27-year-old had only played in 143 NHL games. In those games, he always graded out well analytically, more so offensively (70th percentile offensive on-ice metrics from 2021 through 2024). However, this year, he has exploded, making up the second half of the best defensive pairing in the league.

Final Thoughts

A lot of important developments have happened this season so far for the Devils, but the most important has to be the resurgence of Jonas Siegenthaler. After playing like the worst defensemen in the league last season, it looked like the Devils may have made a mistake locking him up through 2027-28. However, he has put all those concerns to bed, for now, as he has played like the best defensive defenseman in the league through 21 games.

Of course, the analysis of Siegenthaler would not have been sound if his partner in crime was not given his credit. Johnathan Kovacevic’s emergence has played a key role in helping Siegenthaler return to his prior form. This pairing, which is averaging over 20 minutes a night, is key to the Devils ultimate goal of being a contender this season.

Note, all statistics courtesy of Evolving Hockey and Natural Stat Trick.