The 27-year-old back row, who played a big part in Knights reaching the 2016 Championship play-off final, rejoined the Castle Park club this week from Ealing Trailfinders.
He left Doncaster to join this weekend's opponents two years ago after playing a starring role in Knights' spirited two-legged final defeat to Bristol.
Stedman's arrival boosts director of rugby Clive Griffiths options in the back row.
'I welcome back Ollie from Ealing, we're thankful to Ben Ward for letting him join a competitor in the Championship,' said Griffiths.
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'Ollie played some of his best rugby in his last spell here and anticipate he will again now he is more experienced.
'We have been very short on numbers lately as we went into the recent Nottingham game with three hookers in the 22.
'So it is a much welcome addition that Ollie has joined us.'
Samoan international Josh Tyrell and Tongan international Kurt Morath return to the starting XV after spells away representing their respective countries.
New addition Mike Mayhew, another former Yorkshire Carnegie player, is named among the replacements.
Knights have won two out of three in Group 1 of the Championship Cup but dropped to third in the table following last weekend's defeat to Carnegie.
The top two sides in each group, plus the two best third placed teams, progress to the knockout stage.