He was the leading wicket-taker in the 2017 ACC Under-19 Asia Cup with twenty wickets in five matches that helped Afghanistan win their maiden ACC Under-19 Cup title. As a result of this performance, he was named in Afghanistan's One Day International squad in December 2017 for their series against Ireland. He made his ODI debut for Afghanistan against Ireland on 5 December 2017. On debut he took 4 wickets for 24 runs, from his quota of 10 overs, and helped his team win by 138 runs. He was awarded man of the match for his performance. In December 2017, he was named in Afghanistan's squad for the 2018 Under-19 Cricket World Cup. He made his Twenty20 International debut for Afghanistan against Zimbabwe on 5 February 2018. On 16 February 2018 against Zimbabwe at Sharjah, Mujeeb took his maiden ODI five-wicket haul. He became the youngest player ever to take an ODI five-wicket haul and was named the man of the match. In February 2018, the International Cricket Council named Mujeeb as one of the ten players to watch ahead of the 2018 Cricket World Cup Qualifier tournament. On 15 March 2018 in the first match of the Super Sixes at the World Cup Qualifier, he took 3 wickets for 33 runs against the West Indies. He also took a catch off the bowling of Rashid Khan as Afghanistan beat them by 3 wickets, with Mujeeb earning his third ODI man of the match award. During the final of the 2018 Cricket World Cup Qualifier, between the West Indies and Afghanistan, Mujeeb returned with match figures of 4/43 in 9.5 overs, helping Afghanistan to restrict the West Indies to a score of 204. Afghanistan chased the target of 205 losing only 3 wickets with ten overs to spare and clinched its first ICC Cricket World Cup Qualifier title. He was also the joint-leading wicket-taker in the tournament, along with fellow wrist spinner, Rashid Khan and Safyaan Sharif of Scotland with 17 wickets each. Following the conclusion of the Cricket World Cup Qualifier tournament, the ICC named Mujeeb as the rising star of Afghanistan's squad.
Test cricket
In May 2018, he was named in Afghanistan's squad for their inaugural Test match, played against India. He made his Test debut for Afghanistan, against India, on 14 June 2018. Mujeeb became the sixth player, and first for Afghanistan, to make his first-class debut in a Test match. He became the first player born in the 21st century to play Test cricket and also became the youngest player to feature in their country's inaugural Test match.
In April 2019, he was named in Afghanistan's squad for the 2019 Cricket World Cup. Following the World Cup, the International Cricket Council named Mujeeb as the rising star of the squad.
