Sean O'Loughlin and Ben Flower both emerged unscathed from full training sessions to put them on course to return this week.
Captain O'Loughlin has recovered from a torn pectoral suffered at the start of August.
And prop Flower has been sidelined by a minor knee injury he suffered just after returning from a back problem.
Lam is today expected to name them both in his 19-man squad to face Castleford.
But he will only make a call after training tomorrow and admits the fact the game has been brought forward 24 hours - to be televised by Sky Sports - may work against them.
"They're a chance, they both trained last week in spurts, but this was their first full session and they both looked really good," said Lam yesterday.
"It just depend on the pain in the knee for Ben and the strength in the arm for Lockers.
"It would have been ideal for them if we were playing Saturday or Sunday, but it's not to be, and we'll make a call on Wednesday."
Their likely return will mean Lam would only need to drop one player from last Friday's line-up, given Liam Farrell has been given a one-game ban.
Joe Greenwood would seem the most likely candidate to start on the left-side second-row spot in place of Farrell.
Meanwhile, Wigan's Under-19s are set to face Warrington at Robin Park this Saturday lunchtime in their academy semi-final. If they win, the table-topping Warriors will have the right to stage the Grand Final if the DW Stadium is available.
St Helens face Leeds in the other semi-final.