UGO Ehiogu has warned Steve McClaren that he will be "re-evaluating" his future if he is consistently left out of Middlesbrough's first-choice line-up.

The England international will not feature in today's game against Charlton as he has suffered a recurrence of the calf problem that has hampered him all campaign.

But, after becoming increasingly frustrated at his inability to hold down a first-team place, the centre-half will begin to consider his options if he is passed over in favour of Chris Riggott when fully fit.

Injury has restricted Ehiogu to just two Premiership appearances this season, with his last outing coming in last month's 2-1 win over Birmingham.

In his absence, Riggott has impressed at the heart of Boro's defence and, after returning to full fitness, Ehiogu has found himself on the bench during the last two league games against Blackburn and Portsmouth.

The 31-year-old was back in the starting line-up as Boro opened their Carling Cup account with a 3-0 win over Coventry on Wednesday but, speaking immediately after that game, he outlined his frustrations over the way the last month has panned out.

"Hopefully I've done enough to stay in the team for the game down at Charlton," said Ehiogu, before the extent of his latest injury problem became apparent.

"If not, then the picture changes again and it's time to re-evaluate and have a look at things from a different perspective.

"I've got to wait and see. The manager's got some tough decisions to make because people will be coming back into contention after being rested on Wednesday.

"It'll be interesting to see what choices are made and what happens against Charlton.

"I'm not a player who can contentedly sit and watch other players playing in the team - I just can't do that.

"I want to play as many games as possible, but unfortunately that's out of my hands."

This afternoon's team selection is no longer an issue given Ehiogu's latest injury blow, but the situation will arise again once he regains full fitness.

Riggott has done nothing wrong since returning to the first team and, with skipper Gareth Southgate all but assured a starting spot, simple mathematics suggests that three into two will not go.

"It's a recurrence of Ugo's calf injury," confirmed McClaren. "And he has a small tear. He is as upset about it as anybody and we'll be investigating it again on Monday when he sees a specialist.

"He has had a series of niggling injuries since his serious knee injury at the beginning of last season.

"We've been fortunate that we've had Chris Riggott to step in and, even when Ugo has been fit, he has failed to knock him out of the team because he has been doing so well."

With Gaizka Mendieta and Stuart Parnaby on the long-term injury list, McClaren could have done without a further blow ahead of this afternoon's visit to the Valley.

But, while Ehiogu will play no part, the centre-half is confident his side can maintain a fine away record that has seen them lose just twice on their travels all season.

"Our away form has been much better than it was last year," he said. "We're only nine or ten games into the season, but our away form looks like being almost as good as our home form and that's a definite improvement.

"It's pleasing, and it's nice to have an experienced core to the squad. The difference this season has been amazing with the quality that's been brought in."

The current campaign has also seen Middlesbrough's youngsters coming of age in the first team.

Stewart Downing is likely to retain his place on the left flank this afternoon, with Tony McMahon continuing at right-back in the absence of both Michael Reiziger and Parnaby.

James Morrison and Danny Graham underlined their potential with goalscoring contributions to Wednesday night's win, providing strength in depth as Boro continue to chase silverware on four different fronts.

"The younger lads seem to be improving with each game," said Ehiogu. "They're getting more confidence every time they go out onto the pitch and the good thing is that they still want more.

"They've got a real desire and I've certainly been impressed by how far they've come. They've been given a chance and they're grabbing it with both hands.

"I was 18 when I first came through and, to be fair, it's relatively easy at that stage.

"You don't fear anything and you don't worry about anything, so you just go out and play your natural game.

"You're not really expecting to be in the team so, when you are, it's a great bonus, especially when you're finding yourself involved in European games as well."

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