Saitō joined
J3 League club
Fukushima United FC in 2015. On 8 November 2015, he netted a
hat-trick, the first of his career, in a 3–0 win over
J.League U-22 Selection. On 18 December 2015, he moved to
J2 League club
Roasso Kumamoto. He scored on his league debut against
Tokushima Vortis on 6 March 2016, scoring in the 83rd minute. On 13 July 2019, Saitō joined AC Nagano Parceiro on loan. On 8 January 2020, Saitō was announced at Blaublitz Akita. On 17 April 2023, the club announced he was diagnosed with a right hamstring strain and would be out for the next 12 weeks. On 28 June 2023, Saitō scored against
Shimizu S-Pulse in the 49th minute, which was Blaublitz Akita's 400th goal in the J League. On 20 December 2023, Saitō was announced at Fagiano Okayama. He made his league debut against
Tochigi SC on 25 February 2024. Saitō scored his first league goal against
Ehime on 7 April 2024, scoring in the 92nd minute. ==Club statistics==