The most common and most likely answer to this crossword clue is the 8 letter word WORMCAST
I've seen this crossword clue in The Times
W
O
R
M
C
A
S
T
More clues leading to the result WORMCAST
Buddy explains!

The straight part
We know that "On-field evidence of underground move" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case on-field evidence of underground move = wormcast.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.