Morelos will be back for the replay but will miss Ladbrokes Premiership games against St Johnstone and Hamilton either side of the February 20 contest at Ibrox. And Gerrard knows they need to find a way to play to Defoe's strengths.

"They are two different types of players," he said. "They are obviously both very strong in front of goal, but they are very different, so we have to adapt to whoever it is that's leading the line.

"We also have Kyle (Lafferty) in the running as well, maybe we might decide to go down a different way.

"That's for me to work out in the coming days and weeks, but we are definitely in a stronger position when you think about what position we were in with just two strikers in the first six months.

"I'm delighted to have Jermain here, it gives us more firepower, more options to maybe do different things."

Gerrard was satisfied to ensure Rangers are in Monday night's draw, albeit not yet the quarter-finals.

"It's been a hell of a start (to 2019), a tricky start," he said. "You think about our league fixtures – coming here on turf, Livingston away on turf, Aberdeen away, playing on a pitch like Cowdenbeath. We have had a tough start and have had to come here again in the cup on turf on the back of Wednesday night.

"That's the reason I am satisfied because at times you have got to take into consideration what the players have been through.

"But now we have got a run of fixtures, some at home, a replay in the cup, players have got time to recover, and we get ready for St Johnstone."

Kilmarnock manager Steve Clarke was far from despondent about losing home advantage.

He hopes to have striker Eamonn Brophy and defender Stuart Findlay back fit for the replay, while Aaron Tshibola was unable to replace Alan Power when his fellow midfielder suffered a head injury, after the on-loan Aston Villa man suffered a thigh strain in the warm-up.

Clarke said: "We have been to Ibrox already this season and didn't lose. In my time at the club, we always go there, we are always competitive.

"The tie is still open. Rangers will be slight favourites now but we are still in it."

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