Race Comment Explainer

Original comment with matches highlighted:

held up in mid-division, and behind 4th or 5th, ridden and behind 6th,

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
Held up	Intentionally raced patiently at the back to save energy.

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
Intentionally raced patiently at the back to save energy.