Quoting: deys3232
Hanifin didn't break out. He has been near replacement level his entire career. Losing Giordano leaves a massive hole on the Flames blueline
Rielly can fill that, pair him with Christopher Tanev and you have one of the best OFDs alongside one of the best DFDs. Tanev would allow Rielly to run free on offense without having to worry about needing to drop back as fast
Monahan has fallen off a cliff and was heavily carried by Gaudreau. This trade is an absolute steal for the Flames
Honestly you may have been the absolute last person who should have debated whether Hanifin had a breakout season or not
- Hanifin was 12th leaguewide of iCF/60 of defense with at least 500 minutes at 5v5. Post Sutter he was 9th of all dmen who played at least 20 games (~200 min)
- Also post Sutter Hanifin was 26th in p/60 at all strengths of defense who played at least 20 games (excluding Kalynuk since his minutes were very sheltered in Chicago)
- Hanifin was 68th leaguewide in GA/60 (600+ min at EV). For reference Theodore was 63rd, Gio was 65th, Weber 66th, Trouba 69th, Slavin 70th, and Rielly 118th
- He was 79th in xGA/60 leaguewide (600+ min at EV). For reference Josi was 71st, Gio 77th, Makar 78th, Chychrun 80th, Werenski 81st, Ekholm 82nd, and Rielly 143rd
- He was 78th in CF/60 (600+ min at EV). For reference Heiskanen was 71st, Gio 77th, Slavin 79th, OEL 81st, Rielly 85th.
Now before you go and say "Hanifin was carried defensively by Tanev since Tanev was 1st in both GA/60 and xGA/60" you should know that Brodie was 3rd and 19th respectively.
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As for Monahan, he was literally injured 75% of the season. He missed 2 games in the middle of February due to a "lower body" injury and never returned to form after that. Prior to the injury Monahan was pacing 62 points (around his career average) all while still having a career low shooting percentage of 5.56% at the time. Post injury Monahan was pacing 39 points. Monahan has "fallen off a cliff" just as much as much as Pettersson did this year. Injuries tend to do that
Again this trade makes no sense because Rielly is not needed as Calgary is very deep at LD and Monahan is needed as they are very shallow at center