Heartbroken Scotland prop Allan Jacobsen admitted he was "devastated" after being ruled out of the World Cup through injury.

The 28-year-old tore his left calf muscle towards the end of the first half of the Scots' 56-10 defeat of Portugal in their tournament opener in St Etienne yesterday.

The injury will keep the Edinburgh front-row forward sidelined for six to eight weeks, and Scotland have called up Alasdair Dickinson as a replacement.

An inconsolable Jacobsen revealed he sustained the injury as he was packing down for a scrum.

``We went down and I took a couple of steps forward, felt good and then there was a pop,'' he said.

``It felt like someone had poked me in the back of the calf. I knew it was something serious. I have never had this before.

``The scrum came up, I stood up and as I went to step, my leg just gave way.

``I went to stand up again and I couldn't put any weight on it.

``I pretty much knew what had happened. I went to hospital and they told me I had a hole in the muscle.

``I was kind of hoping I'd be all right so I am devastated. It is only the beginning but it is already the end.''

It is the second dose of World Cup agony for Jacobsen. In 2003, the man affectionately known as 'Chunk' was called into the Scotland squad as a replacement midway through the tournament, but did not get on to the pitch in
the three games he was there for.

Four years on and his World Cup lasted around 35 minutes

``I want to at least get 80 minutes of World Cup rugby in my career. If it takes three World Cups, then so be it!'' he added.

``The boys have been great and they are disappointed for me.

``I just hope they do well. I hope they get to the quarter-finals and then anything could happen.''

Scotland team doctor James Robson, who gave the bad news to Jacobsen, maintained the prop's injury was a ``freak accident``.

``He was very unlucky,'' he said. ``And it is devastating for the whole squad. Chunk has worked so hard.

``We all know about the brutal nature of the game, but playing against Portugal is no different to the day-to-day grind of world rugby.''

Scotland assistant coach George Graham added: ``Having seen the boys train, I can honestly say that - bar none - he has probably trained harder than anyone else.

``But with the nature of the World Cup, we have to move on.''

Dickinson, who moved to Gloucester from Edinburgh over the summer, has been involved in one of the Cherry and Whites' pre-season warm-up games to date.

The uncapped prop will be 24 tomorrow.

Graham said: ``Chunk has far more experience. But Alasdair is a lot younger and he is part of the new breed of props.

``He is very fast and is learning all the time. He is definitely one for the future.''

Dickinson, who just missed out on selection for the original 30-man squad, said: ``I'm delighted to be called up but obviously I feel a bit for Chunk because he's a good mate from my days with Edinburgh.''

The defeat of Portugal also left its traces on a number of other Scotland players.

Flanker Allister Hogg has a dead leg but should return to training by the end of the week, while winger Sean Lamont (ankle) and younger brother Rory Lamont (shoulder and hip) are both receiving medical treatment.

Lock Nathan Hines will need a couple of days' rest after damaging his foot and knee, while centre Marcus Di Rollo was left slightly groggy after taking a blow to his neck.

All of these players should be fit for Scotland's next Pool C match, against Romania at Murrayfield on Tuesday week.

Centre Andrew Henderson, who missed the Portugal game with a dead leg, is continuing to make ``slow progress``, according to the Scotland camp.