The most common and most likely answer to this crossword clue is the 6 letter word HOOKER
H
O
O
K
E
R
Buddy explains!

The straight part
We know that "rugby player" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rugby player = hooker.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 HOOKER mean?
HOOKER noun- A rod bent into a curved shape, typically with one end free and the other end secured to a rope or other attachment.
- A barbed metal hook used for fishing; a fishhook.
- Any of various hook-shaped agricultural implements such as a billhook.
- The curved needle used in the art of crochet.
- The part of a hinge which is fixed to a post, and on which a door or gate hangs and turns.
- A loop shaped like a hook under certain written letters, for example, g and j.
- A tie-in to a current event or trend that makes a news story or editorial relevant and timely.
- A snare; a trap.
- (in the plural) The projecting points of the thighbones of cattle; called also hook bones.
- Removal or expulsion from a group or activity
- A field sown two years in succession.
- (authorship) A brief, punchy opening statement intended to get attention from an audience, reader, or viewer, and make them want to continue to listen to a speech, read a book, or watch a play.
- (authorship) A gimmick or element of a creative work intended to be attention-grabbing for the audience; a compelling idea for a story that will be sure to attract people's attention.
- A finesse.
- A jack (the playing card).
- A spit or narrow cape of sand or gravel turned landward at the outer end, such as Sandy Hook in New Jersey.
- A catchy musical phrase which forms the basis of a popular song.
- A ship's anchor.
- Part of a system's operation that can be intercepted to change or augment its behaviour.
- (Scrabble) An instance of playing a word perpendicular to a word already on the board, adding a letter to the start or the end of the word to form a new word.
- A diacritical mark shaped like the upper part of a question mark, as in ỏ.
- A háček.
- Senses relating to sports.
- One who, or that which, hooks.
- A small fishing boat.
- Any antiquated craft.
- A player who hooks the ball out of the scrum with his foot.
- A crocheter.
- A thief who uses a pole with a hook on the end to steal goods.
- A prostitute.
- (1920s to 1940s) An imprecise measure of alcoholic drink; a "slug" (of gin), or an overlarge gulp.