Expression of dismay for oar he’d cracked (2,4)
I believe the answer is:
oh dear
'expression of dismay' is the definition.
(I've seen this before)
'oar he'd cracked' is the wordplay.
'cracked' indicates anagramming the letters.
'oar'+'hed'='oarhed'
'oarhed' anagrammed gives 'OH DEAR!'.
'for' acts as a link.
(Other definitions for oh dear that I've seen before include "Never mind!" , "What a pity!" , "I say" , "rueful remark" , "That's a shame" .)