[4][5] Having progressed through the ranks of Heerenveen's youth academy, he signed his first professional contract on 17 February 2015, penning a three-year deal with the club.

[7][8] Vlap then made his senior debut for the club on 27 November 2016, coming on as a late, second-half substitute for Kosovan international Arbër Zeneli in a 1–0 Eredivisie loss to Ajax.

[9] Vlap failed to appear again during the 2016–17 season but returned to the first team to make his KNVB Cup debut on 20 September 2017, coming on as a substitute in a 2–1 win over Excelsior.

[16] He made his competitive debut for the Tukkers on the first matchday of the 2021–22 season, replacing Dimitris Limnios in the 67th minute of a 2–1 away loss to Fortuna Sittard.

[1][20] On 4 July 2022, Anderlecht and Twente agreed on a permanent transfer and Vlap signed a three-year contract with an option for an additional year.