BLACKBURN Rovers took a giant step nearer the Premiership last night after a thumping 4-1 victory over Grimsby -- but it came at a price as Craig Short became the latest player to join the Ewood casualty list.

Goals from David Dunn, Eyal Berkovic and a Matt Jansen brace saw Rovers open up a four point lead over arch-rivals Bolton with just three games to play.

But manager Graeme Souness was more concerned with the fitness of Short today after the veteran defender twisted his knee in an innocous-looking incident in the 76th minute.

Rovers' medical staff were due to assess the full extent of the problem this morning but Souness has already admitted the former Everton man is a big doubt for Sunday's clash with Portsmouth at Ewood.

And, with Alan Mahon and Stig Bjornebye also facing a race to be fit in time, the sudden spate of injuries has come at a bad time for the Rovers chief.

"Craig caught his knee in between one of their player's legs as he tried to let the ball run out for a goal kick," said Souness.

"So we'll have to wait and see how it is in the next 24 hours but he could be doubtful for Sunday.

"As for Alan, we'll have to see how he is this week but I think he's going to be doubtful for the weekend, too.

"The same also applies to Stig but I'm hopeful we'll see them again before the end of the season."

Rovers turned the screw in the race for second spot after a mistake from Grimsby keeper Danny Coyne put them on the road to another vital victory.

But Souness wasn't complaining after feeling that Lady Luck had deserted his side at the weekend against Wolves.

"I felt a bit sorry for their keeper because he hadn't really done a lot wrong all night until he gifted us that goal," said Souness.

"But sometimes the luck is with you and sometimes it isn't.

"On Saturday it wasn't with us when we bombarded the Wolves goal but couldn't get the breakthrough.

"We got that breakthrough last night by someone making a mistake.

"But we are grateful for that and I think we controlled the game after that.

"When they got it back to 3-1 we became a little bit nervous, sat back too much and allowed them too much possession.

"But, to be fair to my boys, they didn't really cause us too many problems and Brad didn't have to make too many saves."

Rovers are now clear favourites to secure the second automatic spot behind champions Fulham and they could even wrap it up against Portsmouth on Sunday if Bolton were to lose against Barnsley on Saturday.

However, Souness is keeping his feet firmly on the ground and insists there's plenty of hard work still to be done.

"I've been in this business a long, long time and you never get carried away until you've crossed the finishing line," said the Rovers chief.

"If we happen to do that then you'll see me celebrate more than anyone else at the club, but not before.

"We dropped two points on Saturday and if we'd got those then we'd be sitting in an even better position."

"But we are playing good football, we look like scoring goals and we look as if we are enjoying our football, as we have done for most of the season.

"And that's the important thing at this stage of the season. As long as we retain that for another three games then we've got a great chance.

"So that's the pleasing thing from my point of view.

"We're in the box seat now but we were in that before last night.

"We are in the fortunate position that Bolton play on Saturday then we play Sunday. They then play Tuesday and we play Wednesday.

"But whether or not this was a psychological blow, only time will tell. We'll have to see how Bolton play on Saturday before we can say yes or no."