Giants long-snapper Zak DeOssie was wearing a protective boot on his left foot in the locker room on Tuesday.
DeOssie injured his foot during Sunday's win against the Ravens.
LS Tyler Ott, along with the rest of the practice squad, will make the trip to London with the team.
The Giants will have until Saturday to promote Ott to the active roster if DeOssie cannot play.
The Giants signed long-snapper Tyler Ott to their practice squad. ... Long-snapper Zak DeOssie is nursing an ankle injury.- Ralph Vacchiano (@RVacchianoSNY) October 18, 2016
To make room on the practice squad for Ott, the Giants have cut DB Dorian Grant.
Ott spent the offseason with the Giants, and was in training camp with the team until he was cut on Aug. 29.
DeOssie hurt his ankle in Sunday's win over Baltimore, and his status for this week's game in London is uncertain.