Brad Stevens has established himself as a top NBA coach. His Celtics employ horns actions in a variety of ways. Lately, they've been using what I call "Trio"), focusing on the triangle at the top of the key.
I'll show some of their actions and what I expect to see over time.
First, they vary the personnel according to what they're looking to do.
Here, they create drive, pick-and-pop, and roll/slip actions for Al Horford (5).
The 4 (Tatum) burns the trailing defender with a dunk. But if you switch (1/4), Tatum gets a mismatch in the paint.
Jayson Tatum throws the hammer down! 🔨🔨🔨 pic.twitter.com/GBdmcZ4bfq— Boston Celtics (@celtics) January 6, 2018
Here they deploy Irving just above the elbow and the bulky Marcus Smart screens. Irving can cut either way OR come across for a handoff/pick-and-roll with Horford or Baynes (5). If 3's defender helps, that creates an open corner 3.
What I'm expecting soon.
Left, back cut if x4 (defender) looks to overplay.
Right, simple backscreen to (1) Irving (Smart or Rozier) with option for (4) Tatum to pick-and-pop from the top.
What makes the Celtics horns options effective are the multiple talents of Irving, the passing of Horford, and the precocious play of the teenager Tatum.