This document contains the papers presented at MLSA13, which is the rst workshop on Machine Learning and Data Mining for Sports Analytics. The workshop was held at the European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases 2013 in Prague, Czech Republic, and took place on Friday 27 September 2013. There were 13 submissions, covering a wide variety of topics. Each submission was carefully reviewed by at least three program committee members. Based on the reviews, 10 papers were accepted for presentation at the workshop. We are grateful to the authors, the program committee members, and the reviewers for their time and efforts. We would also like to thank the workshop chairs, Niels Landwehr and Andrea Passerini, as well as the conference chair, Filip Zelezny.