The Edmonton Oilers are starting the regular season with a lot of uncertainty with their defensive group.

We know what to expect from Evan Bouchard, Mattias Ekholm and Brett Kulak. But Darnell Nurse is dealing with an injury from the playoff run and isn’t attending training camp. Ty Emberson and Troy Stecher have the potential to be regular options on the right side, which is lacking depth. But there’s no guarantees there. And then there’s Josh Brown, who I wouldn’t have high expectations for considering his on-ice numbers at even-strength, which have consistently been poor. I’m still not sure how he landed a three-year deal.

It remains to be seen how training camp shakes out and if any other players emerge as defensive options, including Travis Dermott, who is on a PTO and Max Wanner, who’s 21, shoots right, and has developed well in Bakersfield. For now, though, it’s the bets management has made and what they have heading into the season. And the Oilers will likely do what they can to accrue cap space and make enhancements to their blueline later in the season – depending of course, on how the current group performs.

If the Oilers do eventually pursue a right-hand defenceman who has term left, I’d suspect they would want someone with experience and someone they have a better handle on. The one name that’s come up a few times in the local market is Finnish defenceman Rasmus Ristolainen. Selected eighth overall in the 2013 entry draft, Ristolainen has played 713 NHL games for Buffalo and Philadelphia. Ristolainen turns 30 this fall and is in the third year of a five year contract he signed with Philadelphia in 2022 with an annual cap hit of $5.1 million.

To make the financials work, the Oilers would probably need Philadelphia to retain a good portion of Ristolainen’s contract, which would cost them extra assets. But before doing that, it’s worth looking at a few things, including Ristolainen’s usage over his career, his on-ice shot-share numbers at even-strength, and what his impacts are on the penalty kill (an area that the Oilers might need help with after the departures of Cody Ceci and Vincent Desharnais). All of this will give us a better sense around what kind of value someone like Ristolainen could bring to the Oilers.

Ristolainen entered the league in 2013 with high expectations and was given a lot of responsibility by the Buffalo Sabres. Management there had done a poor job at constructing the roster, and they didn’t have many options for the coaching staff. So, throughout his eight seasons in Buffalo, Ristolainen played some of the highest minutes in the league and in all situations, especially at even-strength.

Below is the average number of even-strength minutes Ristolainen played by season, with his highest rate of minutes coming as a 22-year-old in 2016-17. Since then, his ice time has gradually declined, especially in his second and third years in Philadelphia, where he’s averaged just over 16 minutes a game. Last season, Ristolainen dealt with significant injuries and played only 31 games, which impacted his ice time. He underwent surgery for a ruptured triceps tendon in April and is expected to be fit to play this upcoming season.

What really stands out from Ristolainen’s time in Buffalo was the extreme amount of time he played against elite-level competition – well above 40 percent in some seasons. He was consistently given some of the highest proportions in the league among defencemen and didn’t fare too well. Again, the Sabres didn’t exactly surround him with good talent, and they missed the playoffs every year because of their shoddy decision-making, so he was typically the best and only option. Below is a breakdown of the competition levels Ristolainen faced using the methodology from PuckIQ.

Philadelphia appears to have recognized that Ristolainen was getting way too much responsibility in Buffalo and had a plan to put him in a position to succeed once they acquired him. In the last few seasons with the Flyers, we see that his proportion of ice time against elite competition has dropped to more reasonable levels – around 30 percent. This is where he probably should have been, considering that his on-ice numbers in Buffalo were so poor.

What this reduced responsibility in Philadelphia appears to have done is help improve Ristolainen’s on-ice shot-differential numbers. Playing so many minutes, and a lot of those minutes against elite competition, Ristolainen played a lot of time without the puck, and his numbers reflected that. The Sabres consistently struggled to outshoot and out chance opponents, and those numbers were even worse when Ristolainen was on the ice. Again, he didn’t have a lot of help on that team. Plus he was definitely in over his head with the assignments the coaching staff gave him.

Below are Ristolainen’s relative-to-team shot-differential numbers by season. I tend to use Corsi, a proxy for puck possession, and Fenwick and Expected goals as a proxy for scoring chances.

We see here that with Ristolainen on the ice, the Sabres fared much worse and saw their shot and chance differentials negatively impacted. Again, a lot has to do with his assignments. But it was painfully obvious that he shouldn’t have played all those minutes and needed fewer minutes and responsibility. When he got to Philadelphia, he did get a lot of minutes in his first season, but as we saw in the PuckIQ numbers, he was playing a lower proportion against elite-level players compared to previous years in Buffalo. What this did was help his on-ice shot-differential numbers, as we saw that the Flyers did better with him than without him. In his second season as a 28-year-old Flyer, his numbers dipped again, but that might have to do with the injuries he sustained and the fact that he’s aging and dealing with some wear and tear.

Another area that Ristolainen has a lot of experience with is the penalty kill. He was regularly on the first unit in Buffalo, and that usage continued during his first two seasons with Philadelphia. What’s worth noting is that while in Buffalo, Ristolainen’s on-ice rate of shots against was quite high relative to his teammates and well above the normal levels for first-unit penalty kills. His numbers, however, have gradually improved since joining Philadelphia, so it might have been the system and linemates in Buffalo that could have been impacting his numbers. If, for whatever reason, the Oilers penalty kill struggles early on, expect Ristolainen’s name to come up more often in the market.

It’ll be interesting to see if we continue hearing about Ristolainen being a potential addition to the Oilers’ right side on the blue line. He’s got the experience and name recognition, and the term left on his current deal would be manageable. However, the Oilers will need to give up assets to have Philadelphia or another team retain part of the salary to make his contract fit. And that’s where the Oilers must determine what value Ristolainen brings and if it’s worth giving up those assets. From his recent numbers, there appears to be value as he can hold his own on a second pairing at even strength and can play on the penalty kill. The one concern with Ristolainen is health, how he recovers from the tricep surgery and if he can stay healthy.

Data: Natural Stat Trick, Puckpedia, PuckIQ