Race Comment Explainer

Original comment with matches highlighted:

led, quickened with one rival from 3f out, headed 2f out, t held inside final ,

Matched phrases & meanings

Phrase	Meaning
Quickened	The horse accelerated and increased its speed sharply.
just held	The horse's powerful late run was not quite enough, and it lost the race by the narrowest possible margin (e.g., a nose or short head).
Kept on	The horse maintained its speed well to the finish.
Furlong	Unit of distance; one furlong is 1/8 of a mile (approx. 200 meters).

Summary

The horse accelerated and increased its speed sharply.
The horse's powerful late run was not quite enough, and it lost the race by the narrowest possible margin (e.g., a nose or short head).
The horse maintained its speed well to the finish.
Unit of distance; one furlong is 1/8 of a mile (approx. 200 meters).