[1] Following the conclusion of the 2017 S.League season, it was announced that Syazwan had signed for local giants Tampines Rovers on a 2-year contract.

He won the 'Man of the Match' award for his outstanding performance against Japanese club, Gamba Osaka and also notably saves 2 penalties in 1 game.

His impressive performance in the 2016 S.League earned him a call-up to the senior squad for the first time in a friendly match against Malaysia on 10 July 2016 by Singapore's head coach V. Sundramoorthy, but did not play.

On 18 June 2023, Syazwan made his second international cap against Solomon Islands at the Singapore National Stadium.

Syazwan's elder brother, Syarqawi Buhari, is a FIFA-certified referee who has officiated in the S.League for a number of years.