Michael Brough missed a penalty and in turn scuppered Forest Green's best chance of claiming all three points against 10-man Tamworth.
The hosts broke the deadlock when Taiwo Atieno rose to head home former Newcastle player Joe Kendrick's inswinging corner from six yards.
Simon Clist headed home Alex Meechan's right-wing cross to equalise.
Gavin McAllum was shown the red card for a foul on Les Afful, but Brough's spot-kick was saved by Sean Bowles.
Tamworth: Bowles, Touhy (Stevenson 63), Kemp, Weaver, Thomas, Kendrick, Deakin, Neilson, McCallum, Williams (Devlin 53), Atieno (Burton 74).
Subs Not Used: Bampton, Storer.
Sent Off: McCallum (50).
Goals: Atieno 12.
Forest Green: Steve Williams, Lawless, Jones, Edwards, Nicholson, Afful (Stonehouse 71), Pitman, Brough (Zarczynski 78), Clist, Russell (Griffin 68), Meechan.
Subs Not Used: Wanless, Preece.
Booked: Russell.
Goals: Clist 47.
Att: 1,215.
Ref: I Scarr (West Midlands).