Fair point, I definitely see the appeal in Tatar as well.
However, consider that Tatar reportedly wants around $5m on his next deal. That doesn't fit with our cap structure as we'd need to send someone packing to make room (not that I'd be against that as you know, but it seems unrealistic for Sakic to do that).
Tatar most likely also wants term, which I don't think Sakic will be keen to give out, unless perhaps if it's 2 years max. This is Tatar's final big payday though so I doubt that he settles for just 2 years.
Now, consider that DeBrusk is an RFA in a years time. You can basically trade Boston a 2nd/prospect + 3rd package, and then very likely flip him in 2022 for a very similar, or better, return when he's an RFA. Chances are that he'll be a good fit on the Avs given the style he plays, and he'll also have the incentive to rebound given that he's in a contract year. So in contrast to the Tatar signing you could basically treat DeBrusk as a one year rental who you get assets back for at the end of the year. Or you just resign him if he does well as he'll still be in his prime at 25 years old.
I suppose you could also sign Tatar to a multi-year deal and then trade him next offseason, but that would be a really good way of ensuring that UFA's are reluctant to sign with your team in the future without NTC's.
Lastly, you posted some good stats there which make a good case for Tatar over DeBrusk, but I'd counter that by pointing out their respective playoff stats which ultimately will be far more important for the Avs than regular season stats.
As you can see below DeBrusk has paced for 22 goals (over an 82 game season) in the playoffs, and 36 points which is right in line with his $3.625m caphit.
Conversely, Tatar has been severely underwhelming in the playoffs, not at all justifying the $5.3m caphit he's had the last 4 years. He's paced for 12+12 and 25 points, well below the value of his contract. He's also been a healthy scratch in the playoffs multiple times in the last 3-4 years.
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