CBS Sports’s Matt Moore put together an interesting piece on Greg Monroe and where he could be dealt. One of the teams he listed was the Celtics. Here’s the reasoning:
The Celtics always want that big-name player without having to actually give up anyone of consequence, and if the Bucks just want to move on, this isn't a bad option. Brad Stevens was able to make Kelly Olynyk into a plus defender last season, and Monroe is at least as talented as Olynyk.
He can play next to Al Horford, who covers up many of his deficiencies, even if rim protection would remain an issue, and the Celtics could land him without giving up "coveted" assets Avery Bradley, Marcus Smart or Jae Crowder (and if they only gave up one of those guards, it's still a good deal).
It's not the sort of player that Boston was hoping for (Jimmy Butler, DeMarcus Cousins, Kevin Durant, etc.) but it is a major upgrade in terms of scoring, which they need, and can be had for what is an acceptable cost.
The logic has some merit but doesn’t seem to take into account two things. One, with the Celtics addition of Al Horford, the team now has Horford, Amir Johnson, Kelly Olynyk, Jonas Jerebko, and Jae Crowder, who makes some cameos in the front court as well. All five of these players are versatile pieces that can play on both sides of the court, something Stevens holds in high regard. But adding Monroe in the mix—though he may be a nice spark off the bench—will strain the other players on the court with him to defend especially well. Bigs who can’t play on the perimeter force other parts of the defense to pay when it comes time to anticipate helping on any mismatch, which can lead to lots of rotation mishaps. This problem especially rears its head in the postseason, where teams pinpoint slow-footed bigs, and continuously run their offense at them— making most unplayable.
To play a little devil’s advocate, one can say that maybe the Celtics’ heavy usage on ICE-ing PnRs could actually hide some of the defensive’s weaknesses that Monroe brings. Though in certain games that could end up working, again, it comes down to how it translates into postseason success. Teams would pin Monroe down and come at him again and again in the playoffs.
Second, there’s the issue of Monroe’s contract, which Moore also noted in his piece. Because he’s essentially on a one-year deal (next year is a player option which he’ll almost certainly exercise). This means that if he proves us all wrong and has a great year, the Celtics would lose him for nothing or sacrifice a big chunk of cap space in a loaded free-agency class on a guy who is best used off the bench. Also, because his contract is just above $17 million, the Celtics would have to give back a pretty big contract back to make it work. A potential Zeller/Jerebko/and rookie contract could work, but is Monroe worth losing the versatility that a Jerebko can bring you? Having Horford makes that extremely unlikely.
Though Monroe could have been an alright contingency plan if the Celtics missed on all of their targets, his acquisition just doesn’t make much sense anymore. Sure he’ll give you close to a potential double-double every night, but his weaknesses won’t allow him to do that for you in a playoff setting consistently. Boston loves the idea of versatility on both the offense and defensive end. Monroe just doesn’t fit the bill.