Race Comment Explainer

Original comment with matches highlighted:

close up towards rear, ridden before 2 out, took 3rd before last where mistake,

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.
Towards rear	Running near the back of the field.
One pace	The horse maintained its speed but could not accelerate or quicken.
Close up	Running very near the leaders (usually 2nd, 3rd, or 4th).
Kept on	The horse maintained its speed well to the finish.

Summary

The jockey started urging the horse aggressively before the second-last obstacle to try and get it back into contention.
Running near the back of the field.
The horse maintained its speed but could not accelerate or quicken.
Running very near the leaders (usually 2nd, 3rd, or 4th).
The horse maintained its speed well to the finish.