Here, the official website of the RBS 6 Nations looks back at the key events in the life of the legendary England prop.

1968: Born August 14, Barking, Essex.

1979: Attended Warren Comprehensive School, Chadwell Heath.

1990: After playing for Barking, England Colts and Eastern Counties, gains England call-up as a Saracens player.

July - Makes Test debut as England beat Argentina 25-12 in Buenos Aires. Aged 21, Leonard becomes England's youngest prop since Nick Drake-Lee in 1963. Three other players also win first England caps against Pumas - Dean Ryan, David Pears and Nigel Heslop.

August - Second cap in 15-13 defeat against Argentina.

November - Wins third cap, also against Argentina, but now a Harlequins player following departure from Saracens.

1991: January - makes his Five Nations Championship debut in 25-6 victory over Wales at Cardiff Arms Park, as England end a 28-year sequence without winning on Welsh soil.

March - Wins first Grand Slam after England defeat France 21-19 in Twickenham thriller.

May - Helps Harlequins lift the Pilkington Cup at Twickenham, with a 25-13 victory against Northampton.

November - Plays in World Cup final at Twickenham, but England beaten 12-6 by Australia.

1992: March - Member of England team that clinches a successive Grand Slams.

Undergoes surgery to rectify a career-threatening neck injury, requiring a bone-graft from his hip.

October - Returns to England team for Test match against Canada at Wembley.

1993: May - On the losing side as Harlequins are beaten by Leicester in the Pilkington Cup final.

June - Heads to New Zealand as part of the British Lions touring squad.

July - Makes his Lions Test debut against the All Blacks in Wellington. Lions win 20-7, but Leonard and his team-mates beaten 30-13 in Auckland series decider a week later.

November - Part of England team that defeats New Zealand 15-12 at Twickenham.

1994: June - Helps England record a stunning 32-15 victory over South Africa in Pretoria.

1995: March - Wins his third Grand Slam in five years as England complete clean sweep with 24-12 success against Scotland at Murrayfield.

June - Part of England team that defeats World Cup quarter-final opponents Australia in Cape Town. But he is on the receiving end as England suffer World Cup semi-final defeat against New Zealand, also in Cape Town.

1996: November - Wins his 50th England cap in 54-21 victory over Italy at Twickenham.

December - Captains England for the first time in Twickenham Test against Argentina after Phil de Glanville withdrew through injury, and scores his only international try as England survive a major fright to win 20-18.

1997: May - Travels on second Lions tour, this time to South Africa. Goes on as a replacement in the first Test, which the Lions win 25-16.

November - New England coach Clive Woodward sees Leonard very much as part of his plans, selecting him for autumn Tests against New Zealand (twice) and South Africa.

1999: October - Features in his third World Cup campaign, including the quarter-final defeat against South Africa in Paris.

2000: November - Overtakes Rory Underwood as England's most-capped player when he makes his 86th appearance against Argentina at Twickenham.

2001: February - On losing side as Harlequins are beaten 30-27 by Newcastle in a gripping Tetley's Bitter Cup final at Twickenham.

May - Selected for third Lions tour, going on as replacement in first and second Tests against world champions Australia in Brisbane and Melbourne, respectively.

November - Becomes the world's most-capped forward, winning his 93rd cap and overtaking legendary New Zealander Sean Fitzpatrick in England's Twickenham rout of Romania.

2002: November - Regains England starting place against Australia at Twickenham following four appearances as a replacement.

2003: February - Earns his 100th cap in England's RBS 6 Nations Championship opener against France at Twickenham.

March - Wins fourth Grand Slam as England beat Ireland in Dublin.

October - Agonises about whether to fly home from the World Cup in Australia to witness the new arrival before partner Sandra gave birth to 8lb Francesca Belle. Decides to stay with the squad because flying home for such a short period would have been disruptive for their two boys, Harry, 4, and Jack, 2.

November 5 - Named in England team to face Wales in World Cup quarter-final, meaning he will equal Philippe Sella's world record of 111 caps for France.

November 16 - Makes world record 112th appearance in semi-final defeat of France in Sydney.

November 22 - Wins World Cup.

December 31 - It is announced he is to receive an OBE in the New Year Honours.

2004: March 9 - Confirms he will retire from international rugby at the end of the RBS 6 Nations Championship.