Biggest change I see has been his batted ball profile.
First 33 games - 25.6% LD% | 33.1% GB%
Last 33 games - 21.6% LD% | 48.0% GB%
For a guy like Nico who doesn’t hit the ball particularly hard, keeping it off the ground is vital.
Nico Hoerner has played in 66 games this season.
His first 33 games:
.301/.375/.466 (.841 OPS)
4 HR, 26 RBI
.289 BA w/ RISP
His last 33 games:
.192/.284./.223 (.507 OPS)
0 HR, 7 RBI
.176 BA w/ RISP
The Cubs were 21-12 during the first stretch, and 12-21 during the last stretch