Rangers turned in a far from convincing display to establish a first leg lead in their Champions League qualifier.
David Weir and Jean-Claude Darcheville celebrate the opening goal
Kris Boyd had hit the woodwork and fired over with the goal at his mercy before David Weir's hopeful lofted pass crept into the net.
Alan Hutton was sent off for two rash bookings inside a minute.
But Rangers increased their advantage when Lee McCulloch's header hit the target, with Zeta keeper Sasa Ivanovic culpable for both goals.
There are unlikely to be two uglier goals scored this season but Rangers manager Walter Smith will be happy to take a lead to Montenegro after watching his side struggle to find any fluency.
Rangers started the match in blistering style and Boyd had slammed a shot against the post inside the first 10 seconds, following a swift move from the kick-off.
The visitors were rattled further two minutes later when Boyd redirected a wayward Charlie Adam drive narrowly wide of the upright.
Adam was guilty of a few poor crosses but came close to a goal when his header from a Hutton delivery was tipped over by Ivanovic.
The Montenegrins recovered from their shaky start and began to string together a few good passing sequences.
Zeta were causing problems with their direct running and there was a scare for the home support when a 22-yard free-kick from Darko Markovic flashed past Allan McGregor's post, with the keeper static.
The second half was four minutes old when Boyd was guilty of the most incredible miss.
Ivanovic could only parry a stinging drive from Barry Ferguson into the path of the Scotland striker but, from seven yards out, he blazed the ball high over the crossbar.
McGregor made a smart save to gather another Markovic set-piece before Rangers took the lead with a bizarre goal on 55 minutes.
Weir simply scooped a loose ball into the danger area from the edge of the penalty box and, under pressure from Jean-Claude Darcheville, Ivanovic took his eyes off the ball and allowed it to bounce beyond him into an empty net.
Having enjoyed a lucky break, Rangers immediately suffered a setback when Hutton was foolishly sent off.
The right-back was booked for a clumsy challenge and picked up a second yellow card for charging down the resultant free-kick.
However, the 10 men continued to press forward and were rewarded with another strange goal.
McCulloch out-jumped the calamitous Ivanovic and, with Nacho Novo clattering into a defender who was shaping to clear, the ball again trickled into an unguarded net.
The final 15 minutes were played at a tepid pace as Rangers comfortably closed out a game they laboured to win.
Rangers: McGregor, Hutton, Weir, Cuellar, Papac, McCulloch, Ferguson, Hemdani, Adam (Novo 45), Boyd (Broadfoot 63), Darcheville (Sebo 83). Subs Not Used: Carroll, Webster, Thomson, Beasley.
Sent Off: Hutton (60).
Booked: McCulloch, Hutton, Novo, Cuellar, Hemdani.
Goals: Weir 55, McCulloch 73.
Zeta: Sasa Ivanovic, Igumanovic, Miroslav Kaludjerovic, Vuckovic, Radulovic (Djurovic 78), Tumbasovic, Cetkovic (Boljevic 84), Markovic, Bojan Ivanovic, Korac, Stjepanovic. Subs Not Used: Mustur, Vladen Pelicic, Zarija Pelicic, Culafic, Marinkovic.
Booked: Vuckovic, Tumbasovic, Radulovic.
Ref: Georgios Kasnaferis (Greece).