IT is to be hoped that Martyn Waghorn's agent had the foresight to negotiate a generous goal bonus into his client's Rangers contract, with an added extra built-in for penalty kicks. The Geordie striker has never had a reputation for being prolific - indeed his previous best seasonal tally is 12 - but by the end of September in his first season in Scottish football he already has 14 goals, with no fewer than seven of them coming from the penalty spot. It is enough to rekindle the memory of Marco Negri's race to 30 goals by the Christmas of '97.

Waghorn left with the match ball and the man of the match champagne as the Ibrox side made light of this potentially tricky assignment at Cappielow to establish a nine point lead at the top of the division ahead of the visit of their closest challengers Falkirk to Ibrox next weekend. There was plentiful praise for the 25-year-old former Wigan player both from his manager and his team-mate Andy Halliday, who revealed that Waghorn's perfect penalty ratio was actually at his expense.

"We have been winding him up about the penalties," said Halliday. "The sad thing is I’m second on the penalties so I’m choking for him to come off and let me have a shot. If he’s not on the park I take them but he is playing 90 minutes most weeks. We practised penalties in training and it was between the two of us and he got the nod. But that’s seven from seven penalties now so he’s different class and he deserved his match ball. I’m happy to let him do it when he’s got a conversion rate like that. He practises them every day and reaps the benefits. It’s really important you have a striker than can score 25 goals a season and he looks like he’s on the way to hit that target."

The TV cameras were at Cappielow for first league meeting between these two sides since the 1987-88 season. The Greenock side had won that encounter 3-2 and hopes were high in home areas at the end of a week which saw them progress to the last eight of the League Cup after extra time at the expense of Premiership side Motherwell, while the Ibrox side were dumped out of the same competition at home by St Johnstone. While Rangers' Championship form has been impeccable so far this season, Morton had lost just on league match previously themselves, by a solitary goal at Easter Road to Hibs.

Mark Warburton made one change to his starting line-up, bringing in Barrie McKay - once on-loan to a Morton side who got relegated from the Championship - for Kenny Miller and this was a chastened Rangers team who emerged for this lunchtime kick off, greeted by the visiting fans with plumes of blue smoke. Jim Duffy had taken a page from the Tommy Wright playbook, leaving two mobile strikers up the park to try to occupy Rangers' central defenders, while the pacy Bobby Barr was stationed wide left in an attempt to get into the space behind James Tavernier.

While the approach was periodically successful in creating chances, it placed too great a strain on Morton as a defensive unit, particularly with on-loan Barclays Premiership duo Nathan Oduwa and Gedion Zelalem showcasing their abilities to the full. The Arsenal kid had already had a shot saved by the time his Spurs pal produced the piece of skill which turned this match. Picking the ball up on the right flank, Oduwa eliminated Connor Pepper too easily then drove into the box before drawing a rash challenge from the lunging Ross Forbes. Referee Willie Collum had no hesitation and penalty specialist Waghorn slotted in his seventh such spot kick of the season.

Say what you like about Waghorn, but he isn't half racking up the goals. His 13th of the season in all competitions arrived from open play, from another scenario in which the brawny striker is comfortable in. Fed by McKay in the football equivalent of the low post in basketball, he held off Ricki Lamie, then swivelled to fire in a low left-foot shot which left Gaston with no chance.

Forbes curled a free-kick into the sidenetting, but when Morton got caught up the field from a similar position, this match was seriously getting away from the home side. Tavernier started the counter attack, winning a header inside his own box, and finished it too, slotting in a left foot finish, after the ball had been funnelled onto him via McKay and then Zelalem.

The Ibrox side were in a comfort zone by now, but there were still glimpses of defensive frailty. Samuel pounced on a Rob Kiernan mistake but the Welsh striker, on-loan from Swansea, who had been a cup hero in midweek, got it all wrong from just outside the six yard box. Foderingham produced a fine double save from Michael Tidser and Denny Johnstone, but the former Celtic youth striker really should have given him no chance.

Home goalkeeper Derek Gaston saved well from Waghorn and substitute Kenny Miller, but the second half was mainly a non-event. That was until Tavernier got down the right one last time, his cross was missed by Miller and Waghorn gobbled up goal No 14 of the season with a finish which deflected into the top corner. Substitute Dean Shiels struck a post late on but this was job done for Rangers, who had re-established their old routine following the trauma of midweek.

Morton (4-4-2): Gaston; Kilday, O'Ware, Lamie, Pepper; TIdser, Miller, Forbes (McCluskey 67), Barr (Sabajo 75); Johnstone, Samuel (MacDonald 67).

Subs not used: Adam, McKee, Scullion, Russell

Rangers (4-1-2-3): Foderingham; Tavernier, Kiernan, Wilson, Wallace; Halliday; Zelalem (Shiels 62), Holt (Miller 62); Oduwa, Waghorn, McKay (Law 76).

Subs not used: Kelly, Ball, Law, Clark, Aird

Referee: W Collum

Booked: Morton: Forbes 60, O'Ware 84

Attendance: 7,392