Leeds suffered a further setback in their bid to be promoted on Tuesday eveningComing from behind, Marcelo Bielsa's side rescued a 1-1 draw against Luton Town.A game that on paper they should have won, the Whites failed to build on the momentum they'd gained from the 3-0 win over Fulham last weekend.One positive was that Leeds managed to open their advantage at the top of the table to four points with West Brom not in action until later in the week.A point is better than none, but it showed that the Yorkshire club may still have an element of caution in their minds.Most disappointing was the double injury blow that Leeds suffered against the Hatters.Liam Cooper was withdrawn after just 12 minutes for Gaetano Berardi and then Stuart Dallas went off to be replaced by Jamie Shackleton deep into injury time.After the game, Phil Hay took to his Athletic Q&A to confirm that it didn't look like good news for the duo.CooperTelling supporters about their two injuries, he revealed: "Need to check on them. Dallas seemed to be holding his hamstring. Cooper looked to be in a lot of pain too. Concerns." It was hugely worrying to hear this, even if it more concrete news on their injuries was revealed by Hay further into yesterday evening.Taking to Twitter, the journalist added:

GIVEMESPORT'S Matt Dawson says...

Given Leeds' lack of depth throughout the squad, having two injuries to contend with certainly won't help. 

Cooper, first of all, is the club captain and a pillar of solidity, earning a place in the PFA Team of the Year last term.

As for Dallas, he has been one of the Whites' most reliable players this season, so losing him for the Blackburn clash isn't good news.

The Northern Irishman scored the equaliser against Luton on Tuesday and his extreme versatility, being able to play in the middle of the park as well as at full-back is invaluable.

That was evident in midweek as Dallas started on the left before being put on the right for the second half when Berardi came off.

Having players like that is a huge boost to the squad and they'll have to deal without him at the weekend.

Presumably, Gjanni Alioski will replace Dallas on the but that remains to be seen.