Williamson hoping to start
Lee Williamson could return to the Portsmouth starting line-up for the visit of Preston.
The midfielder shook off a calf problem to feature as a late substitute in the 2-2 draw at Tranmere last weekend.
Defenders Mustapha Dumbuya (knee) and Gabor Gyepes (heart palpitations) were also passed fit to face the leaders so caretaker boss Guy Whittingham has a full-strength squad to choose from.
Simon Eastwood is expected to keep his place in goal after an impressive display, meaning recent signing Phil Smith will be on the bench again.
Midfielder Darel Russell and forward Jake Jervis will be facing their former club.
Pompey are without a win in nine matches but have drawn their last two having lost the previous seven.
Manager Graham Westley has hinted that Nicky Wroe and Lee Holmes may struggle for Preston.
Although both players were able to play in North End's 3-1 defeat to Crewe last week, Westley revealed that the midfield pair are struggling.
Wroe has been missing training sessions after having a scan on his knee with Westley conceding his performances have dropped as a result.
The Lilywhites boss also announced Holmes is troubled with an illness which may result in him being unable to play the full 90 minutes at Fratton Park.
Preston will continue to be without defender Scott Laird (broken leg) and Keith Keane (knee) as the pair are long-term absentees.
Westley has been impressed by Pompey, despite their off-field problems.
"They've got some tremendous players there with great backgrounds and great qualities," he told Preston's official website.