Skipper Lee Wallace has told the Rangers support to expect even more out of forward Harry Forrester as the season progresses.

The former Doncaster and Brentford attacker made a slow start to his Ibrox career after signing in January on a six-month deal.

But he has exploded into life over the past week with three goals in as many games to help keep Mark Warburton's side on course for promotion as well as sparking the 4-0 rout over Dundee which has booked Gers' place in the last four of the William Hill Scottish Cup.

Warburton admitted his new signing had struggled in his first few weeks in Glasgow after trying too hard to impress his new team-mates.

But having followed up his last-gasp winner against St Mirren last weekend with strikes against Raith Rovers and then Paul Hartley's Dees, Light Blues captain Wallace can see the confidence surging through his veins.

And he expects his new team-mate to get even better and better as Rangers chase a Ladbrokes Championship, Petrofac Training Cup and Scottish Cup treble.

He said: "I'm really pleased for Harry in particular. He is another one who has come in and added tremendous work ethic. He has added real value on and off the pitch. He's a great lad, very down to earth, and he's now getting his rewards for his hard work on the pitch.

"He can play anywhere across the front. Seven, nine, 10 or 11 and can perform well too. He's obviously a very technically gifted player as we've seen with his goals. He's done really well and there's a lot more to come from him.

"You could say the goal against St Mirren has settled him down. Everyone wants to impress and he's certainly done great in recent weeks to get his confidence to where it is now.

"But we're a confident group. We won't take anything for granted, we want to kick on and win important games coming up."

Forrester, playing in a central midfield role, inspired Gers to victory in the 2-0 win over Rovers last Tuesday which moved them 14 points clear in the race for automatic promotion.

He was back out on the right hand side of Warburton's front three for Saturday's cup clash with Dundee and took just 13 seconds to smash the hosts in front at Ibrox as Gers stormed into the semi-finals.

Those displays have also impressed strike partner Kenny Miller, who claims he could see 25-year-old Forreser was inching towards making an important impact even during his underwhelming start to life north of the border.

Miller told the official Rangers website: "Harry has been great. It's maybe taken him a few weeks to find his feet and get his fitness, but even before that I think he was very, very unfortunate not to open his account in the Morton and Alloa games as he was fantastic in those matches and hit the post and had a few chances.

"In the last three games though he has been outstanding and the goals have been a massive part of us firstly moving on today and also securing three points in the league as well."

Rangers' crushing win over Dundee was another statement of intent as they prepare to make their top-flight return.

But Hartley could not explain why his Premiership side fell so flat in Govan after claiming a creditable 0-0 draw at Celtic Park on Wednesday.

He said: "We are coming into a quarter-final, a magnificent chance to get into a semi-final and they didn't perform. It's pretty simple.

"Rangers were good, I've got to give them credit, they played really well today. They were after us, on the front foot but some of the goals we lost [were very disappointing].

"We've been good defensively recently but today it just wasn't the case and I can't explain that, I can't put my finger on it.

"The players have been really good up until today, they had a really strong performance on Wednesday night and in the previous six or seven games and then today when it really counts, [they didn't turn up]."