Jimmy Calderwood's Aberdeen side go into the CIS League Cup semi-final against Dundee United at Tynecastle tonight with a brighter outlook than they had a week ago when the tie was postponed because of a waterlogged pitch.

Then, there were only enough fit players available to assemble a 16-man squad and while a hamstring injury to Jamie Smith towards the end of yesterday's training session is a serious blow, the Aberdeen manager's disappointment at his absence is tempered by the emergence of Josh Walker. The midfielder signed on-loan from Middlesbrough just a few days ago until the end of the season has already shown - in Saturday's Scottish Cup victory over Hamilton Academical, that he has the attributes to make a huge impact during his stay in Scotland.

Indeed, a request by England Under-19 coach, Brian Eastwick, for the 18-year-old to be released for tonight's friendly against Croatia at Swindon, was politely rejected by Calderwood who views the Geordie as crucial to his plans for the semi-final.

Walker could not supress his delight last night at being involved in the the first team so soon after his move north, a temporary transfer he feels will enhance his football education following the acceptance that forcing his way into the Middlesbrough side was unlikely at this stage of his career.

"I've had to settle in quickly," he said, "because we have so many games coming up. That's why I came here, because I want to be involved in big games and while we didn't play well against Hamilton, the main thing is we got a result and it was nice for me to play and I did all right and enjoyed it.

"When I first heard of Aberdeen's interest I wanted to come straight away. That was at the start of January. Then it kind of fizzled out because Middlesbrough weren't going to let me go due to injuries among the midfield players and they thought they would need cover. But deep down I knew I wasn't going to be involved.

"When the chance came I was pushing Gareth Southgate, the manager, to be allowed to go and he eventually agreed."

Walker admitted to being impressed by first division Hamilton, and accepts that it will be even tougher against opposition in the top league.

But he has overcome his share of adversity, in the shape of career-threatening injuries, to shine as one of the England youth set-up's brightest talents and is keen to make a bold impression in Scotland.

"I didn't want to be staying in the reserves all season as I wanted to test myself and there is no bigger test than coming to Aberdeen and playing against the likes of Celtic, Rangers, the semi-final against Dundee United and the UEFA Cup matches against Bayern Munich. I mean, what more could you ask for?"

The indications are that Walker and another on-loan signing, Alan Maybury, brought in from Leicester City, will start tonight.

Calderwood felt the departure of Barry Robson from Dundee United to Celtic had dealt the club a better hand than they otherwise might have had, though he was quick to point out that such a change in circumstances may just galvanise the Tannadice side.

"On paper, it has strengthened us," he said, "but there are times when we've thought we were really strong and we simply haven't performed the way we can."

Mark Kerr, the Dundee United midfielder, knows people are expecting his team's fortunes to dip following the departure of Robson, but he believes winning through to the CIS Cup final would prove those detractors wrong.

United's goalless Scottish Cup draw at St Mirren last weekend was taken in some quarters as proof of a lack of punch now their midfield talisman is gone.

However, Kerr has revealed the United players have developed a resolve to prove they have been more than a one-man show all season.

"We've had to wait a while for this game to come around and we were disappointed that it wasn't played last week but things like that can't be helped," said Kerr.

"We've lost Barry during that time but we're still a good team and things have to go on. We knew what the headlines would be after the St Mirren game if we didn't win two or three nil.

"Barry took all the free kicks and corners so he was involved a lot in our play. He was a big player but, over the next few weeks, I'm sure the boys can step it up and show everyone we're capable of doing it from other areas of the park.

"The best thing we can do now is use a high-profile game like this to put a show on, get to a final and demonstrate the progress we've made."

Craig Levein, the Dundee United manager, will be without cup-tied January signings Danny Swanson and Danny Grainger, and first-team regulars Noel Hunt, Willo Flood and Sean Dillon are all injury doubts.

"Noel has a knee knock but I'll think he'll be okay," revealed Levein. "Bigger concerns are Sean Dillon and Willo Flood who picked up ankle knocks at the weekend.

"We'll give them until the afternoon but I think they'll struggle to make it. That leaves us a bit short at right-back because if Sean wasn't playing there Willo would.'' Levein's attempt to sign David Forde from Cardiff is dead in the water.

The United manager had sent a submission to FIFA after the SFA denied him the chance to sign the goalkeeper because of the ruling preventing players turning out for three clubs in a season, but now the FA have thwarted the appeal, and Levein accepts the matter is closed.