Attachment theory (Bowlby, 1969/1982, 1973, 1980) asserts that people are born with an innate psychobiological system (the attachment behavioural system) motivating them to seek proximity with significant others (attachment figures) in times of distress. Individual differences in attachment can be measured along two dimensions; avoidance and anxiety, representing the degree to which hyperactivating or deactivating strategies are used as alternative strategies for regulating emotion. People who score low on both dimensions are considered more securely attached, while higher scores on either or both dimensions reflects more attachment insecurity. Forrest (2008) proposed that insecurely attached athletes might be more susceptible to performance deficits under competitive stress compared to securely attached athletes. This study examined whether attachment orientation would predict performance under pressure on a sport motor task. Sixty-four competitive basketball players shot 20 free throws under low and high pressure. It was hypothesized that attachment orientation to parental figures and closest teammate would predict performance changes. Regression analyses showed that attachment orientation was not a significant predictor of performance change under pressure. However, the manipulation check revealed that competitive anxiety did not sufficiently increase from low pressure to high pressure, and significant changes in performance between conditions were not found. This may suggest that the manipulation of high pressure was not realistic or severe enough to threaten the attachment behavioural system in competitive athletes. Results showed that athletes’ attachment orientation to mother correlated with attachment orientation to their closest teammate. Discussion surrounds the difficulty of manipulating pressure in sport research as well as avenues for future research on attachment and sport performance