[1][2] Itoje began his career in 2012 when he signed his inaugural professional contract with Saracens, quickly making his debut the following year.

At international level, Itoje has been a key figure in two British & Irish Lions tours, securing nominations for the prestigious World Rugby Player of the Year thrice.

[3][4][5] Additionally, he has played a pivotal role in England's success with a Grand Slam and multiple Triple Crown victories, solidifying his reputation as one of rugby's exceptional talents.

As a schoolboy, Itoje played several sports including basketball, football, rugby and athletics, representing England at the U17 level in shot put.

Itoje also played a starring role in the summer series win against Australia, starting all three tests, and was subsequently named the World Rugby Breakthrough Player of the Year for 2016.

[27] Itoje was again instrumental in England's defence of the Six Nations title in 2017, this time starting all five games as a blindside flanker rather than his more usual second row.

He was again selected for the 2021 British & Irish Lions tour to South Africa,[5] which the tourists went on to lose in the closely fought third game decider.

[35][36] In January 2025, Itoje voiced his support for the Six Nations to stay on free-to-air television, expressing that rugby should be a game that is accessible to everyone.

[38] He is mobile and agile for a lock forward, with the capacity to get into wide channels, make breaks through his speed, and claim turnovers in the ruck.