The most common and most likely answer to this crossword clue is the 10 letter word METHUSELAH
I've seen this crossword clue in The Times
M
E
T
H
U
S
E
L
A
H
More clues leading to the result METHUSELAH
- Hamlet's hue troubled the old man
- Ancient writer, so well recalled
- Old man with a lot of bottle?
- Everyman ‘so robust’: on the contrary, he reached age of 969!
- Everyman – so healthy! – knocked back enormous quantity of booze
- Encountered silence about beer rejected for large bottle of wine
- Old man showing a lot of bottle
- He must heal sick old man with bottle
- Old man from Maine so well in retirement
- Indulgence in unsuitable liquor — note, it didn’t shorten his life!
Buddy explains!

The straight part
We know that "the old man" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the old man = methuselah.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 METHUSELAH mean?
METHUSELAH noun- A wine bottle having the capacity of eight standard bottles (six litres)