But, thankfully, Forest Green's teamsheet also showed no Matty Stevens, their top scorer also injured at the weekend.
Oates has been nursing a thigh injury and aggravated it in Saturday's 1-0 win at home to Northampton Town.
Jordan Bowery came in to replace him tonight while, in the only other change, Kieran Wallace took over from Ryan Stirk in midfield with Stirk dropping to the bench.
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Experienced defender James Perch was also back on the bench after missing the weekend with illness.
This was the third attempt to stage the fixture with the first date in December called off due to the high number of Covid cases at Forest Green and then in January the rearranged game was abandoned shortly after kick-off due to a heavy fog descending on the New Lawn.
FOREST GREEN: McGee, Wilson, Sweeney, Cargill, Stevenson, Adams, Aitchison, Cadden, Matt, Moore-Taylor, March. SUBS: Thomas, Bernard, Young, Hendry, Godwin-Malife, Diallo, McAteer.
STAGS: Bishop, Hewitt, O'Toole, Hawkins, McLaughlin, Wallace, Quinn, Longstaff, Lapslie, Bowery, Akins. SUBS: Stech, Rawson, Perch, Stirk, Maris, Law, Johnson.