Morelos’ absence meant that Jermain Defoe led the line for Rangers, but he had scant supply in a first half in which Kilmarnock came close to taking the lead on several occasions. The first arrived within two minutes of kick-off when Conor McAleny ambushed Ross McCrorie in midfield and strode on to thrash a drive from 25 yards which swept narrowly over the crossbar.
Chris Burke also came close with a deceptive free-kick which forced an equally-adept save from Allan McGregor, but, almost on the half hour, the goalkeeper was beaten during a manic flurry inside the Rangers box which saw four point-blank efforts repelled, the closest coming from Youssouf Mulumbu, whose low drive was booted off the line by Andy Halliday.
The prize opportunity, though, fell to James Tavernier from the penalty spot when Kirk Broadfoot handled a Scott Arfield shot on the deck. Tavernier, who scored twice from the spot against St Mirren last weekend but also hit the post, struck his effort down the middle where Daniel Bachmann stuck out a leg to block.
The remainder of the evening was no more fruitful, with the better openings falling to Rangers but not exploited. Joe Worrall was offered an unchecked header at a corner kick but pushed it wide of the post when it seemed simpler to score and Defoe, too, should have done better when he broke into the box one-on-one against Bachmann but rolled his finish wide of the far post, as the contest moved inexorably towards a replay which both sides could do without.
The day’s earlier action in the Scottish Cup saw Partick Thistle take their place in Monday’s quarter-final draw when they edged a hard-fought contest with East Fife with a single goal by Steven Anderson. Hibernian also booked their spot in the last eight with a home win over Raith Rovers and were set on their way by first-half strikes from Daryl Horgan and Vykintas Slivka.
Euan Murray gave Raith brief hope but it was extinguished when Marc McNulty scored his first goal for Hibs in a 3-1 victory. In Paisley, St Mirren were embarrassed by Dundee United of the Championship, who finished 2-1 winners with goals from Olag Safranko and Nicky Clark, despite being down to 10 men when Callum Butcher was sent off after an hour.
The Sunday cup schedule will see Celtic at home to St Johnstone in the lunchtime kick-off between two teams who will be meeting for the third time in 11 days, with the Hoops having won both league encounters 2-0, at Parkhead and McDiarmid Park.
Later in the afternoon, Hearts are at home to junior side Auchinleck Talbot, a tie that evokes memories of the game between the same sides in January 2012, when the Ayrshire side lost 1-0 but had a last-minute goal by Gordon Pope ruled out because of an offside decision which TV replays showed to be incorrect.