Goalkeeper Sam Lomax scored a late leveller as Town emerged from a dramatic encounter at Butlin Road with a point after they clawed back a 3-0 half time deficit against unbeaten Quorn.
The visitors were clinical in the first half punishing Rugby with their only three chances, but Valley recovered well in the second - with their other goals coming from Dylan Parker and Ryan Seal.
Quorn took the lead after just five minutes when Leke Shodunke was afforded far too much time and space on the left hand side before cutting in and smartly poking a shot past the wrong-footed Lomax via the inside of the post.
Charlie Evans then broke free down the middle as the hosts looked to promptly square things up, but he shot straight at Max Culverwell - with Keenah Rosser another to warm the visiting keeper's hands with an effort from just inside the box.
However it was the visitors that scored next when Stephen Hart dinked a cross over Lomax to allow Leavi Oshungbure to bundle the ball home at the back post.
Quorn appeared to have put the game out of Valley's reach just past the half hour mark when Lomax was again slow to react to Tawanda Mangondoza low effort after the visitors had countered swiftly.
Rosser blazed one off-target ahead of the half-time whistle, although Rugby started the new period with renewed vigour and Parker was soon reducing the arrears when he fired the ball neatly home after a nice lay-off from Seal.
Town continued to push back the Quorn defence but often found their final ball was lacking incision, whilst at the other end aside from a side footed volley over the bar from Hart, the away side offered little of threat.
Seal then saw a decent finish chalked off for offside and Danico Johnson curled a dangerous effort just wide.
Parker was the next to miss out when his touch saw him lose control of the ball when running through on goal, with sub Justin Marsden and Lee Thomas both missing the target with wild shots from dangerous positions.
Marsden did provide the valuable assist to allow Seal to complete a fine move from the home side with a strike from the edge of the penalty area for Rugby's second.
With the momentum well and truly with Valley now, chances continued to come their way and Parker lifted one agonisingly over.
The departure of Hart to the sin bin for dissent gave Town a numerical advantage for the closing portion of the game, and the equaliser came from an unlikely source when the towering Lomax ventured forward for a late Seal corner - whereby he rose perfectly to meet the ball and head it home.
There was still time for a Rugby winner, but Johnson lashed Liam Francis's header across the box into the back of the stands.
Line-up: Lomax; Rosser, L Thomas, Recci, Francis; Hancocks (Marsden), Elliott; Parker, Evans, Seal; Johnson. Subs not used: C Thomas, J Thomas, Padmore,. Booked: Francis, Parker.
Quorn line-up: Culverwell, Dawson, Phillip, Oshungbure, Alexiou, Bryant, Mangondoza, Dale, Shodunke, Hart, Sarkodee. Subs: Suttie-Corbette, Mwanyongo, Mason. Marshall, Moyo.