Defending world and Olympic 800m champion David Rudisha has announced he is withdrawing from next week's IAAF World Championships in London due to a quad muscle strain injury.

Its sad and disappointing to announce my no show in the forthcoming #london2017 WC due to a quad muscle strain. pic.twitter.com/bdM0Zi4QCd

— David Rudisha MBS (@rudishadavid) July 31, 2017

Rudisha has had a slow start to his 2017 season, having his only win come from a 1:44.90 showing in Hungary. Though Rudisha has experienced early-season difficulties in the past only to perform his best at worlds, this year he will be sitting out during the championships. 

This is the second time that Rudisha has skipped a season's IAAF World Championships the year following the Olympics, as he also skipped 2013 Worlds due to injury.

It is unclear whether or not this development will allow his compatriot Michael Saruni -- UTEP teammate of Kenyan Trials champ Emmanuel Korir -- to attend London after he was left off the team despite finishing in 3rd place. Saruni was not named as a Kenyan 800m alternate on the official IAAF entry lists released Saturday.

We'll keep this article updated with further developments.