Ottawa Senators Top 25 Under 25, #11: Lassi Thomson

Coming in at #11 in this year’s edition of our Top 25 Under 25 ranking is one of the candidates for the right side this year in Lassi Thomson.

Top 25 Under 25, #11: Lassi Thomson (Reader Rank: 11, Last Year: 19)

Yesterday, we read about Jacob Bernard-Docker coming in at #12 and today we’ve got the other young right shot defender eyeing a spot on Ottawa’s blueline: leaping up a few spots up to #11 is Tampere native Lassi Thomson. Over the past few years, Thomson has been sitting steadily in the late teens as one of the defensive prospects that was tough to get a read on — primarily because he was bouncing around different leagues and playing at times inconsistent hockey.

After all, between 2018 and 2022, over the course of four full seasons, Thomson suited up in four different leagues including the WHL, Liiga, AHL and NHL. That’s a lot of disruption and some massive changes in both quality of competition and quantity of ice time. After settling into a top four role in Belleville two years ago, Thomson came into 2021-22 with the confidence from Belleville management that he could be leaned on as one of their top defenders at just 21 years of age. While he spent the majority of the year in the minor leagues, he had a few cups of coffee with the big club where he performed well enough to launch himself into a serious conversation about being a full-time Ottawa Senator as early as October — pending his performance in camp.

Under the tutelage of Head Coach Troy Mann, Thomson has turned into a well rounded defender at the AHL level. He saw season over season improvement in his primary point production, hopping from 0.26 to 0.36 P1/GP. While 46% of his production did come on the powerplay, what’s most impressive about Thomson’s DY+3 season is how the Belleville Senators, at even strength, were more successful than not with Thomson on the ice as he rocked a 54.10 EV GF%.

Offensively, Thomson’s greatest attribute has always been a heavy shot. Whether he has time for a slap shot or not, Thomson is able to get the puck to the net, enabling his forwards to crash for rebounds or, in some cases, beating the goalie outright.

The NHL is where things got interesting for Thomson. As with every prospect of his age and pedigree, Thomson had to go from playing big minutes on the top pair in Belleville to playing soft minutes, usually in rotation, at the NHL level. His deployment does make his numbers in the big leagues look a bit rosy, which is understandable, but I still think it’s important to note that Thomson led all Senators defenders in CF% with 50.46. Again, his quality of competition was lower than that of someone like Artem Zub or Thomas Chabot, and he only played 230 5v5 minutes (compared to 1240 for Chabot, for example) but the results were there.

During his 16 games with the Sens last year, Thomson played a shift or two with a number of players but the majority of his even strength ice time (55%) was spent with Chabot. After Chabot, his most common partners were Dillon Heatherington (11%) and Nick Holden (8%). So, while Thomson definitely didn’t have the toughest competition, it’s not like DJ Smith put Chabot out against bottom of the barrel players just so he could feel comfortable with Thomson on the ice. There was trust earned there, and Thomson and Chabot combined for 56.08 CF% as a duo.

Enough about the numbers, there’s something about Thomson’s game that could hold him back from being a regular, top four defender in the NHL and it’s not something you measure through shot shares, heat maps or anything else. It’s pace.

In any scenario where Thomson had a bad shift or a bad game last season, you can visit the game tape and see that it was primarily due to his inability to keep up with the speed of the NHL. It’s not to say that he is a slow or poor skater because his stride is actually quite good. And it also isn’t a case where he’s so behind the play that he’s coughing up pucks or making blatant errors. It’s that he hasn’t yet shown that he’s able to effectively move the puck and lift his teammates up through his distribution from the back end. When you see a player like Zub, who isn’t an offensive dynamo, get the play moving from the back end, he’s able to see the ice well enough that he will find players in transition and thread the puck through a seam. Thomson does this well with time, but with pressure the puck is more likely to be off the glass and out or sent into the feet of a teammate more than you’d like.

If Thomson can overcome this, he can be a great option on the right side with someone like Chabot. Positionally, Thomson plays well and when he’s got time and space, he’s really effective. If he can get that extra half step in his game and read the play a little quicker, we’ve got a full-time top four rearguard on our hands. The difference between “guy who can play in the top four” and “guy who should play in the top four” is all about pace and I know DJ Smith and his staff will be looking at this closely as training camp opens up in a couple of weeks.


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