AUTHOR=Calleja-Gonzalez Julio , Lalín Carlos , Cos Francesc , Marques-Jimenez Diego , Alcaraz Pedro E. , Gómez-Díaz Antonio José , Freitas Tomás T. , Mielgo Ayuso Juan , Loturco Irineu , Peirau Xavi , Refoyo Ignacio , Terrados Nicolas , Sampaio Jaime E. TITLE=SOS to the Soccer World. Each Time the Preseason Games Are Less Friendly JOURNAL=Frontiers in Sports and Active Living VOLUME=2 YEAR=2020 URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2020.559539 DOI=10.3389/fspor.2020.559539 ISSN=2624-9367