Junior was included in the Easterns cricket team squad for the 2015 Africa T20 Cup. In August 2017, he was named in Durban Qalandars’ squad for the first season of the T20 Global League.
On 26 April 2018, he was called upon to replace the injured fellow South African seamer, Chris Morris for the Delhi Daredevils team for the rest of the 2018 IPL season.
In June 2018, he was named in the squad for the Titans team for the 2018–19 season. In October 2018, he was named in Nelson Mandela Bay Giants’ squad for the first edition of the Mzansi Super League T20 tournament. In March 2019, in the semi-finals of the 2018–19 Momentum One Day Cup, he took career best figures of 6/19 against Cape Cobras, to help Titans progress to the final of the tournament. . In February 2018, he was named in South Africa’s Twenty20 International (T20I) squad for their series against India. He made his T20I debut for South Africa against India on 18 February 2018. In June 2018, he was named in South Africa’s One Day International (ODI) squad for their series against Sri Lanka. He made his ODI debut for South Africa against Sri Lanka on 8 August 2018.
In August 2019, he was named the Momentum One-Day Cup Cricketer of the Season at Cricket South Africa’s annual award ceremony. In September 2019, he was named in the squad for the Nelson Mandela Bay Giants team for the 2019 Mzansi Super League tournament. In April 2021, he was named in Northerns’ squad, ahead of the 2021–22 cricket season in South Africa