Martyn Waghorn notched up the second hat-trick of his Light Blues career through a fine strike and two penalties. It also saw the 25-year-old move onto 25 goals for the season with three months of the campaign still to play.
Captain Lee Wallace put Gers ahead within 20 minutes before Barrie McKay added a second, a goal capping off an impressive performance from the 20-year-old. The visitors did have their moment at 2-0 when Dean Brett curled a brilliant free-kick into the top corner but Rangers responded to close the game out.
The result means Mark Warburton’s team will be in the hat for Monday’s draw as they go in search of the club’s first Scottish Cup since 2009.
Waghorn caused an early scare in the fourth minute when he tried to whip a shot into the top corner. The striker’s effort went just inches high of the apex as he looked for his 23rd goal of the season.
But it was four minutes later that Rangers really tested Jamie Sneddon with some intuitive football. A quick sequence of play inside the box saw Jason Holt thread the ball to McKay before he slotted Kenny Miller through on goal. The striker, who netted a hat-trick last time out, was quick to react and side-footed goalwards but the keeper saved well with an outstretched leg.
With 18 minutes gone Rangers made their 95% possession show as Miller and Wallace combined to give Gers the lead in classy style. The veteran forward threaded the eye of a needle through the Cowden’ defence and picked the captain up as he hurtled in from the left. Wallace cooly and calmly finished past Sneddon, sending the ball nestling into the bottom corner.
Just under 10 minutes later the pair were linking up again, this time working their way from the left flank into the penalty area. Miller started wide and a series of zigzag passes between them found Wallace one-on -one with Sneddon again, this time though the keeper managed to save at his feet.
Rangers kept surging forward and Zelalem had a chance to open his account too but his shot from close range was blocked as his search went on.
But it wasn’t long before the light Blues had two, McKay creating his own goal from out on the left just after the half hour mark. He cut inside and skipped into the box with relative ease to lift the ball and place a curled shot inside the far post.
Five minutes before the break the visitors had their best chance of the half to make an impact and make it they did. Dominic Ball brought Greig Spence down on the edge of the area in a perfect position. Brett stepped up to take the free-kick and struck a cracker. He curled it right-footed to lift it up and over the wall, before the ball bounced against the underside of the bar and over Wes Foderingham’s line – the keeper stayed rooted to the spot.
Waghorn nearly struck back immediately when he struck one on the turn but he dragged it wide of the upright.
The in from striker was back at it again within a minute of the second-half starting. James Tavernier played him in and Waghorn dinked and dived to take the ball to the by-line and cut back for Miller. His close range effort was straight at the keeper though and the Blue Brazil cleared the danger.
Within two minutes of that the former Wigan and Leicester man was on target. Zelalem flicked the ball to him and he hurried the ball across the top of the box, beat his man and then unleashed a superb curling shot beyond Sneddon. Rangers were back in control.
Holt was keen to add his name to the score sheet too when he tried one from 25 yards and tested the keeper, who did well to hold. The diminutive middle man was involved again minutes later as Zelalem went agonisingly close. Holt got to the by-line and handed the Arsenal loanee a guilt edged chance but he fired straight at Sneddon.
On 54 minutes Fraser Kerr tripped Tavernier inside the box and Rangers were handed their umpteenth penalty of the season. Waghorn stepped up and dispatched the spot kick, squeezing it between keeper and the right post to give him 24 for the season and Gers four for the afternoon.
With Cowdenbeath tiring and offering very little it was becoming an easy task for Warburton’s men. Then with 13 minutes left to play Rangers had their second penalty of the game. Christopher Kane felled Tavernier as the right-back went for goal and the referee immediately pointed to the spot. Waghorn stepped up again and sent a bullet of a penalty past Sneddon to give him his hat-trick.
RANGERS: Foderingham, Tavernier, Wallace, Ball, Zelalem (Forrester 62’), Miller (Hardie 71’), Halliday (Shiels 62’), McKay, Holt, Wilson, Waghorn.
Subs not used: Gostomski, Kiernan, Law, Thompson
Goals: Wallace 18’, McKay 34’, Waghorn 48’ 54’ 78’
COWDENBEATH: Sneddon, Donaldson, Kerr, Scullon, Adamson, Brett, Hughes, Milne (Kane 56’), Callaghan, Smith (Johnston 72’), Spence.
Subs not used: Roman, Zubaidi, Yakub, Beaumont, Armstrong
Goals: Brett 40’
Yellows: Hughes 18’