Barry Robson’s initial attempt cannoned off the defensive wall to the feet of substitute Karim Kerkar who bumped into Dado Prso before collapsing dramatically to the turf.
This time Robson made no mistake with the set piece, spearing in a venomous drive that ended 812 of scoreless resistance from Klos and left the Light Blues trailing league leaders Celtic by seven points after an afternoon of toil and struggle for Alex McLeish’s men.
United, lying 11th in the SPL, celebrated the point as if they had clinched the championship itself leaving Rangers to rue a flawed afternoon in front of goal where they dominated their opponents without ever looking like killing them off.
Novo’s inclusion in the team had seemed to be more by accident than design, with the official team sheet listing Peter Lovenkrands in the starting 11 and the Spaniard as one of the substitutes.
The late switch almost paid dividends after just two minutes when Novo easily beat Mark Wilson to send in a deep swirling cross from wide on the left flank.
Prso rose well to divert a header across the face of the goal only to watch the ball lick the far post and bounce to safety.
With confidence coursing through the side after the 5-0 trouncing of Amica Wronki in midweek, it seemed only a matter of time before Rangers went on from that bright start to open the scoring but they were to be tightly shackled by an organised United defence and the occasional unwanted intervention of the offside flag.
Two wild long-distance attempts way off target from Gregory Vignal and Fernando Ricksen’s free kick straight at Paul Jarvie were all Rangers could manage in a lacklustre opening half hour after a fervent start that had hinted at much more.
United, with only one victory to their name all season, were understandably more proficient in defence than in attack.
As he sought to earn his eight consecutive clean sheet, Gers captain Klos probably expended more energy contesting the toss of the coin ahead of kick-off than he did in the 88 minutes that followed as United defended 10-deep to keep Rangers at bay.
Even when the United backline occasionally faltered – as they did when Jarvie spilled a Bob Malcolm cross eight minutes before the interval – no-one in Light Blue was able to take advantage.
Moments later and the keeper found himself under pressure again, unconvincingly parrying Novo’s fierce drive only for Prso to bundle the rebound over from a tight angle.
With little sign of the stalemate abating, McLeish waited until just nine minutes after the re-start to make his first alteration, Steven Thompson replacing the ineffectual Shota Arveladze.
Thompson’s introduction sparked fresh impetus into an ailing Rangers side although two mis-hit Chris Burke crosses soon after had the groans echoing around the stadium again.
Despair was to quickly become joy, however, when the Light Blues made the breakthrough with 68 minutes played.
Vignal threaded a pass through to Novo and the Spanish striker shrugged off an insipid challenge to rocket a right-footed drive past Jarvie and into the top corner of the net.
It was a quite exquisite strike – a virtual replica of his goal against Kilmarnock earlier in the month – sullied only by the ridiculous decision to book the goalscorer afterwards for the apparent crime of celebrating with kit man, Jimmy Bell.
Rangers could have been two up minutes later when Thompson dived headlong to connect with a teasing Burke cross only for the ball to skew agonisingly wide of target.
It was to prove to be a telling miss when Robson’s late equaliser stunned Ibrox once more into silence.
Rangers threw everyone forward and looked to have a decent shout for a penalty after Thompson collided with David McCracken in the penalty box but referee Steve Conroy waved away the claim.
With time ticking down, the Light Blues were awarded a free kick just outside the United penalty box only for Malcolm to send his effort high into the stand to end Rangers’ late rally.
RANGERS (4-4-2): 1 Klos; 15 Khizanishvili, 4 Boumsong, 5 Andrews, 24 Vignal; 17 Burke (Namouchi 86), 2 Ricksen, 12 Malcolm, 10 Novo; 7 Arveladze (Thompson 53), 9 Prso
Subs not used: Smith, McLean, Hughes, Ball, Campbell
Booked: Novo (69)
DUNDEE UNITED (4-4-2): 24 Jarvie; 2 Wilson, 5 Archibald, 25 Innes, 3 McCracken; 8 Brebner, 14 Dodds, 4 McInnes, 11 Robson; 9 Samuel (McIntyre 73), 16 Grady (Kerkar 79)
Subs not used: Hirschfeld, Duff, Ritchie, Gardiner, Robertson
Booked: Robson (58), Samuel (59), McInnes (90)
Rangers’ Man of the Match: Nacho Novo