AEK Athens Tselios began his career at the infrastructure segments of
AEK Athens, and made his senior debut against
Pannaxiakos on the last matchday of the
2013–14 Gamma Ethniki season. He played for
AEK's U−20 during the club's short tenure in the
Football League and eventually made his
Super League debut in 26 November 2016, as a late substitute for
Patito Rodríguez in a 3−0 home win vs.
Platanias. In total, Tselios made 4 appearances for the club in both the Super League and
Cup competitions.
Loan moves At the start of the
2017–18 season, Tselios moved to fellow Super League side
Lamia on a one-year loan deal in order to get more playing time. He was subsequently loaned out to
Football League side
Ergotelis in January 2018 until the end of the season. He became instrumental in
Ergotelis' Second Round push out of the relegation zone, making a total of 18 appearances, all as a starter. On 16 May 2018 he scored his first goal for the team in a 2−1 away loss against
Anagennisi Karditsa. On 20 May 2018 he scored in a 5−1 home win against
Aiginiakos, which cemented his team's place above the relegation zone. His performances with the club made
Ergotelis officials request an extension to his loan from
AEK, therefore securing Tselios' services until the end of the 2018−19 season.
Ergotelis Having proven himself to be an invaluable asset for
Ergotelis' style of play, the club's administration pushed for his acquisition via transfer from
AEK. Their perseverance eventually paid off, as Tselios was released from his contract with
AEK, and joined
Ergotelis on a two-year deal in September 2019. ==Personal life==