Message from old flame in 'Times' (4)
I believe the answer is:
text
'message' is the definition.
(I've seen this before)
'old flame in times' is the wordplay.
'old flame' becomes 'ex' (an ex-lover).
'in' means one lot of letters goes inside another.
'times' becomes 'tt' (two abbreviations for time).
'ex' going into 'tt' is 'TEXT'.
'from' is the link.
(Other definitions for text that I've seen before include "Words of a book" , "inspiration for sermon" , "Written material for study" , "Written communication" , "Book or play prescribed for study" .)