Race Comment Explainer

Original comment with matches highlighted:

tracked leaders on inside, st 3rd insid over 2f out, lost 3rd inside final ,

Matched phrases & meanings

Phrase	Meaning
Tracked leader	Followed closely behind the leaders.
Pushed along	The jockey started to urge the horse (hand-riding, not necessarily using the whip).
Plugged on	Kept going without showing much pace.
Furlong	Unit of distance; one furlong is 1/8 of a mile (approx. 200 meters).

Summary

Followed closely behind the leaders.
The jockey started to urge the horse (hand-riding, not necessarily using the whip).
Kept going without showing much pace.
Unit of distance; one furlong is 1/8 of a mile (approx. 200 meters).