Walked with Stewart to the junction (4)
I believe the answer is:
trod
'walked' is the definition.
(treading is a kind of walking)
'stewart to the junction' is the wordplay.
'stewart' becomes 'rod' (I've seen this in other clues).
'to' says to put letters next to each other (I've seen this in other clues).
'the junction' becomes 't'.
'rod' put after 't' is 'TROD'.
'with' is the link.
(Other definitions for trod that I've seen before include "Pressed (grapes) by foot" , "Pressed (something) down with the feet" , "Walked upon" , "Trudged, stepped" , "Walked heavily, put foot down" .)