Pick up second athlete at the centre? (5)
I believe the answer is:
heart
'the centre?' is the definition.
('heart' can be a synonym of 'centre')
'pick up second athlete' is the wordplay.
'pick up' becomes 'hear' (synonyms).
'second athlete' becomes 't' (2nd letter of 'athlete').
'hear'+'t'='HEART'
'at' acts as a link.
(Other definitions for heart that I've seen before include "Muscular organ - compassion" , "It's in the chest" , "one needs to beat" , "Vital organ - centre - courage" , "Cardiac courage" .)