TONY Mowbray has been forced to promote three youth-team players into his Middlesbrough squad for this evening's Capital One Cup fourth-round tie with Sunderland.

Marvin Emnes became the latest player to join Boro's lengthy injury list when he damaged his hamstring in the first half of Saturday's 2-1 win over Bolton.

The Dutchman joins Jonathan Woodgate, Rhys Williams, Kevin Thomson Julio Arca, Mustapha Carayol, Luke Williams, Curtis Main and Lukas Jutkiewicz on the sidelines, with Josh McEachran also ruled out of tonight's game because he is cup-tied.

As a result, Mowbray has promoted teenagers Christian Burgess, Ryan Brobbel and Matty Dolan from the development squad, and while the trio are unlikely to feature at the Stadium of Light, their presence underlines the extent of Boro's injury concerns.

"We've added three kids to the squad who haven't played for us yet," confirmed Mowbray. "They've been doing well in the under-21 league and we are down to our last 18 players.

"We are a bit threadbare at the moment, and we will basically be putting out the team we've got.

"I need to try to protect one or two players because you have to be very careful of the workload you put on to players coming back from injury. We don't have a lot of options, but we will pick a competitive team."

Understandably, promotion is Boro's overriding ambition this season, and Saturday's Championship trip to Charlton will be at the forefront of Mowbray's mind as he ponders his starting line-up at the Stadium of Light.

But having pushed Sunderland close in two FA Cup games last season, only to eventually succumb to an extra-time winner from Stephane Sessegnon, Boro will make the short journey up the A19 with nothing to fear.

A win tonight would take them into the League Cup quarter-finals for the first time since 2005, and after Cardiff City made it all the way to the final of the competition last season, recent history proves that a place in the Championship is no barrier to success.

"Our main agenda this season is to do well in the league," said Mowbray. "But when a local derby comes along and the reward is a quarter-final, it's not to be sniffed at.

"It's a big challenge for us, but we are in a confident mood at the moment. Our morale is high and we've won four on the bounce now. While they have all been tight games, sometimes it helps when players find an extra yard to win a game like that because it brings them closer together."

Sunderland have not won many tight matches recently, in fact they have not won many matches full stop with their only successes this season coming against Wigan, Morecambe and MK Dons.

Nevertheless, Mowbray is full of admiration for Martin O'Neill's squad and feels it is only a matter of time before they come good.

"They have some very talented players who can individually hurt you," he said. "We haven't played against many £12m strikers this season or £10m wide players - they have quality to hurt you.

"We will need to show huge concentration, but still have to ask questions. If we can get our noses in front like last year, we can make it an uncomfortable night for them. It's an opportunity for us to get a big scalp, although I'm sure Martin and his players are aware of that and won't want it to happen."