Race Comment Explainer

Original comment with matches highlighted:

led, quickened 5th, ridden before 3 out, headed 2 out, disputing 3rd and beaten last, flat

Matched phrases & meanings

Phrase	Meaning
ridden before	The jockey started urging the horse aggressively before the second-last obstacle to try and get it back into contention.
Quickened	The horse accelerated and increased its speed sharply.
Weakened	The horse lost speed and dropped back through the field.

Summary

The jockey started urging the horse aggressively before the second-last obstacle to try and get it back into contention.
The horse accelerated and increased its speed sharply.
The horse lost speed and dropped back through the field.