The most common and most likely answer to this crossword clue is the 8 letter word BEFRIEND
I've seen this crossword clue in The Daily Telegraph
B
E
F
R
I
E
N
D
More clues leading to the result BEFRIEND
- Find beer possibly as favour
- Look out for GI avoiding complex debriefing
- Help to turn around end of tiresome day
- Get close to a possibly brief death
- Get intimate with kinky ref in bed covers
- Support fire damaged in arch
- Show goodwill to be right when devil’s around
- Support surprisingly brief conclusion
- Side with brief shot in front of goal
- Favour leader in fun run that’s entering turn
Buddy explains!

The straight part
We know that "Support" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case support = befriend.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 BEFRIEND mean?
BEFRIEND verb- To become a friend of, to make friends with.
- To act as a friend to, to assist.
- To favor.