Wayne Gray is also likely to remain in Williams' starting XI while top scorer Adam Boyd may again have to settle for a place on the bench after recovering from a recurrence of an ankle problem.
Fellow forward Dean Morgan missed both games over the Easter period after taking a knock in training last week but is now available.
When the two sides met in December, JJ Melligan netted to give the O's a share of the spoils in a 1-1 draw at Sixfields.
Struggling Northampton will be without midfielder Giles Coke.
Stuart Gray's side increased their relegation troubles with a 3-2 defeat at home to Southend on Monday which left them three points adrift of safety.
Coke missed that defeat with a calf injury and he is still out, so Gray could name the same midfield at Brisbane Road.
Striker Scott Vernon is struggling with a thigh strain he picked up against Southend so Aleksandar Prijovic could return to the starting XI.
The on-loan Derby man hit his first goal for the Cobblers after coming on for Vernon on Monday and is in line to partner top scorer Adebayo Akinfenwa.
Midfielder Luke Guttridge is back in training after a knee injury but is unlikely to be fit enough to feature.
Sporting Life