He made his professional debut at age 21 with South Africa's Northern Free State Griffons, playing 49 matches from 1999 to 2001.

In 2001, Lensing was selected for the South African National Rugby Union Team, the Springboks, U/23 Group, but had to withdraw due to a knee injury.

He also made his debut for the Namibian National Side during this time (2002), and at age 25 he represented Namibia at the 2003 Rugby World Cup as first choice loose head prop.

[9] However, at the end of his first season with Leeds, Lensing exercised the opt-out release clause in his contract and was aggressively recruited by the Sharks.

[10] He returned to South Africa to play for the Sharks in the Super 14 in 2006, generating controversy surrounding a reportedly high salary that was allegedly leaked to the media by a competing agent.

[11] Brian Smith, then-director of the London Irish, publicly criticized[12] Lensing for the move, claiming that he had agreed to play for the Exiles.

In 2008, Lensing signed with Castres Olympique (France) in the Top 14 French rugby union league.

In 2010, after helping Namibia qualify for the 2011 Rugby World Cup, Lensing announced his retirement at the age of 32.