Race Comment Explainer

Original comment with matches highlighted:

rear of mid-division, behind 10th, out, pulle 12th, 4 out, after

Matched phrases & meanings

Phrase	Meaning
Mid-division	Running in the middle of the pack.
not fluent	The horse jumped the tenth fence/hurdle poorly or awkwardly
tailed off	A definitive statement that the horse was finished and effectively out of the race
pulled up	The jockey stopped the horse from continuing
Rear	Running near the back of the field.

Summary

Running in the middle of the pack.
The horse jumped the tenth fence/hurdle poorly or awkwardly
A definitive statement that the horse was finished and effectively out of the race
The jockey stopped the horse from continuing
Running near the back of the field.