Starts to play yorkers later on: now this holds things up (5)
I believe the answer is:
pylon
'this holds things up' is the definition.
'starts to play yorkers later on now' is the wordplay.
'starts to' indicates taking the first letters.
The initial letters of 'play yorkers later on now' is 'PYLON'.
(Other definitions for pylon that I've seen before include "Tower carrying electric cables" , "Structure supporting power cables" , "It marks turning point in a race" , "Power cable support" , "Grid cable support" .)