The most common and most likely answer to this crossword clue is the 6 letter word TACKLE
I've seen this crossword clue in The Times
T
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More clues leading to the result TACKLE
Buddy explains!

The straight part
We know that "Grapple with/gear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case grapple with/gear = tackle.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.
What does TACKLE mean?
TACKLE noun- A device for grasping an object and an attached means of moving it, as a rope and hook.
- A block and tackle.
- Equipment (rod, reel, line, lure, etc.) used when angling.
- (by extension) equipment, gear, gadgetry.
- A play where a player attempts to take control over the ball from an opponent, as in rugby or football.
- A play where a defender brings the ball carrier to the ground.
- Any instance in which one person intercepts another and forces them to the ground.
- An offensive line position between a guard and an end: offensive tackle; a person playing that position.
- A defensive position between two defensive ends: defensive tackle; a person playing that position.
- A man's genitalia.
- To force a person to the ground with the weight of one's own body, usually by jumping on top or slamming one's weight into him or her.
- To face or deal with, attempting to overcome or fight down.
- To attempt to take away a ball.
- To bring a ball carrier to the ground.
- To "hit on" or pursue a person that one is interested in.