Honestly, when you go through the list of trades made during the Glen Sather era, they really aren't bad at all. He made way more great value trades than bad ones. Big money signings are another thing though...
The worst trade of the Sather era was probably Cally and picks for MSL, but really, if MSL doesn't come over and his mom doesn't die, we probably don't go to the Finals. Was seeing our team in the finals worth giving up Cally and two picks? I'd take that deal again because I'll never forget that run.
Remember, at the time Sather was trading an underperforming, overpaid third liner in Cally for two playoff runs and a full season of the reigning Art Ross champion who, at that moment, was having another great year with Tampa. He fizzeled out with us but was instrumental in the Cup run. Even money as far as I'm concerned.
Nash trade was a steal for us, not even close to a bad trade.
Yandle trade was good. Again, our window was closing, and Yandle had a great playoffs and has generally been very good for us, AND we can still flip him for assets. Once again, not even close to a bad trade.
Here are some really bad ones that Sather made (some were already mentioned):
Boatload of picks for Ryan Clowe.
Nigel Dawes, Dmitri Kalinin, and Petr Prucha to Arizona for Derek Morris.
Alexei Kovalev for Josef Balej (Seriously, that's all Kovy was worth? At least Neil Smith got Petr Nedved back for him the first time!)
Leetch trade was terrible in hindsight, but more because we didn't do much with those draft picks and the prospects turned out to be "eh." So, good trade, bad scouting?
Kovalev and Leetch should have netted us more than we got during a supposed rebuild.
Neil Smith Era
Bar none, the worst era of trades in NYR history. The 1994 Cup glosses over what was a spectacularly bad era of management for the Rangers. Smith's horrendous trades were only to be outdone by his laughable draft choices.
Right away, my choice for worst trade in modern NYR history (wasn't alive for Middleton) is Zubov AND a young Nedved (who went on to score 99 points with the Pens and, when he came back to us for Kovy, produced some high scoring seasons for one of the league's worst offenses. He doesn't get enough credit) for Ulfie and Robitaille. Doesn't get much worse than that. Zubov was being compared to Bobby Orr in 94. Nedved was the next Jagr. Obviously those two things didn't happen, but Zubov was a star and Nedved went on to become one.
Marc Savard and a 1st for Calgary's 1st, Jan Hlavac, and their third round pick that we wound up trading back to them, who wound up being Craig Anderson. Actually doesn't look like that terrible of a trade considering who we technically got back, at least not compared to other bad trades of ours, but still...Savard went on to be elite and Hlavac was just good.
Cloutier, Sundstrom, 2000 1st rounder, and 2000 3rd rounder for the pick that became Pavel Brendl. This is another hindsight is 20/20 trade analysis, but that was a lot to give up on a risk player in what was quite possibly the weakest draft class in NHL history.
Kloucek, Rem Murry, and Marek Zidlicky for Mike Dunham. God, and we wondered why we were always desperate for that elite puck moving defenseman. The hangup over Zidlicky was the fact that Neil Smith didn't want to sign him to a ONE YEAR guaranteed contract. On a team that sucked. Seriously?
Mike Knuble for Rob Dimaio. Knuble was like the Kreider of his time. "26 and he still hasn't figured it out! He never will! Guys are already in their prime by 22! Trade him!" Except he did figure it out, and became a regular 28-30 goal scoring 6'3 power forward for the Bruins and other teams.
"We need power forwards who can score! We need puck moving defensemen!" Yup.
And to think that if we didn't win the Cup in 1994, the top three trades on this list might be the Amonte, Gartner, and Weight deals. All abysmal, as was Todd Marchant for Craig MacTavish, but the Cup...
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Other trades that come to mind:
Norm Maciver, Brian Lawton, and Don Maloney for Carey Wilson and a 5th round pick. Actually not terrible considering how good Wilson was for us that first half year, but in retrospect he was finished not long after while Maciver went on to become a reliable offensive threat from the blueline. Led the terrible 93 Sens in points! lol
Granato and Sandstrom for Nicholls was awful, except Nicholls got us Messier.
The Ridley trade was bad.
Tinordi for Lawton, bad.
We also traded Dave Ganger for spare parts which turned out to be a disaster. Maybe our worst trade of the 80s.