Pieter Willem Adriaan Mulder (born February 19, 1998), known as Wiaan Mulder, is a South African cricketer. He made his One Day International (ODI) debut for the South African national cricket team in October 2017, before making his test cricket debut in March 2019. Domestically, he plays for Highveld Lions and Gauteng.

Domestic career

Mulder made his world-class cricket debut at The Wanderers for Highveld Lions against Cape Cobras in the Sunfoil Series 2016-17 in October 2016 while he was still in school. He took seven wickets on his debut, including 3/10 in the Cobras' first innings. Prior to his debut, he was part of the South African squad for the 2016 U19 World Cricket Championship. He made his Twenty20 (T20) debut for Highveld Lions at the CSA T20 Challenge 2016-17 in November 2016 and his List A debut at Momentum One Day Cup 2016-17 in February 2017.

In June 2018 he was appointed to the roster for the Highveld Lions team for the 2018/19 season. In September 2018 he was appointed to Gauteng's squad for the Africa T20 Cup 2018. In May 2019, Mulder signed with the Kent County Cricket Club to play in the 2019 County Championship in England. He played three games for Kent before being recalled to the South African team before the international fixture list.

International career

In October 2017 he was inducted into South Africa's ODI squad for their series against Bangladesh and made his international debut on October 22 at the age of 18. In February 2018 he was called up in South Africa's test squad for their series against Australia, but did not play and was called up in the squad of Twenty20 International (T20I) for the one-off game against Sri Lanka in August 2018, but did not play in the game again.

In January 2019, he was reappointed to South Africa's T20I squad, this time for their series against Pakistan, but did not play. Mulder was reassigned to South Africa's squad in February, this time for her test run against Sri Lanka. He made his test debut on February 21, 2019 against Sri Lanka.

In April 2021, Mulder was inducted into South Africa's T20I squad for the series against Pakistan. He made his debut at Twenty20 International (T20I) for South Africa on April 16, 2021 against Pakistan.

In September 2021, Mulder was named to the South African squad for the 2021 ICC Men's T20 World Cup.