Born in
Concepción, Rojas began his career with
Cerro Porteño. In April 2013, he signed a 5-year contract with Portuguese club
Benfica, joining at the start of the 2013–14 season. After playing for
Benfica B in the
Segunda Liga, he was loaned to
Belenenses in January 2014 for the rest of the season. On 8 July 2014, Rojas was loaned to Argentine club
Gimnasia LP until December 2015. He made 51 appearances and scored 5 goals for Gimnasia between July 2014 and December 2015. Upon his arrival back to Benfica he was again sent out on loan, as he joined former club Cerro Porteño. In January 2019 Rojas signed for Mexican club
Querétaro. On 24 June 2019,
Tijuana announced his signing on a 18 months loan. On 3 January 2020, Rojas returned to Paraguay, joining
Club Olimpia. On 9 June 2021, he joined
Sol de América. On 22 July 2022, Rojas returned to Paraguay joining
Sportivo Ameliano, after a failed stint at
Metalist Kharkiv due to the start of the
Russo-Ukrainian War. ==International career==