[8] He made his first-team debut on 25 July, as a 59th-minute substitute during AZ's 0–0 home draw against BK Häcken in the second qualifying round of the Europa League.

[9][10] At AZ he was mainly utilised as a right back, where he competed with the older Jonas Svensson, and was set to become his future successor.

[8] On 4 August 2019, Sugawara started in the home match against Fortuna Sittard and scored the final goal in the 84th minute, to make it 4–0 after preliminary work by Calvin Stengs.

On 23 February 2020, it was announced that Sugawara would sign a five-year contract to join AZ permanently from 1 June 2020.

[18] He made his debut with the senior Japan national team in a friendly 0–0 tie with Cameroon on 9 October 2020.