The Texans become the 31st side out of 32 teams to play in London today. The Green Bay Packers are the only side not to have graced London yet.
Read Alex Finnis' piece on how despite being London's latecomers, why the Texans have the steel and superstars to win over a British crowd
The defensive end was having a superb season before it was cut short last week against the Oakland Raiders.
Watt tore a pectoral muscle ending his season which is a huge blow to a Texans side which serious play-off ambitions. The ability for the Houston defence to pressure the quarter-back is radically reduced by the lose of Watt.