MIDDLESBROUGH manager Steve McClaren has warned Danny Mills against becoming embroiled in a vendetta against Arsenal in tonight's Carling Cup first leg semi-final at Highbury.

Gunners winger Robert Pires lit the touch-paper for a potentially explosive occasion when he branded the Boro right-back "a whinger''.

Mills was accused of gamesmanship when he confronted Thierry Henry as the Arsenal striker was about to take a penalty in the Gunners' 4-1 Premiership victory at Highbury ten days ago.

The England defender also clashed with Pires and was later humiliated by Henry, who performed an outrageous dragback through Mills' legs as they tussled for possession near a corner flag.

Pires said: "Mills went whingeing to the referee, Andy D'Urso, saying it wasn't a penalty and that Patrick Vieira had dived.

"Then he went up to Thierry, saying he was going to miss the kick.

"Once Thierry had scored, he went over to Mills to tell him what he thought of him. In the end, we made him look ridiculous when Thierry nutmegged him at the corner flag.''

Arsenal manager Arsene Wenger is set to field a youthful side tonight, with Henry rested and the likes of Vieira and Pires not expected to feature.

But, regardless of the Gunners' line-up, McClaren has dismissed talk of further trouble and revealed he has urged Mills not to rise to any baiting from the opposition or home fans.

McClaren said: "Danny knows what kind of reaction to expect after his performance there ten days ago.

"We've had a long chat about it and he knows what to do - he's experienced enough. There'll be no problem.''

On-loan Mills, who McClaren is trying sign on a permanent basis from Leeds, is vital to Boro as the manager grapples with a defensive crisis.

Skipper Gareth Southgate and Colin Cooper are ruled out with hamstring injuries and Ugo Ehiogu is only given the slimmest hope of recovering from the groin problem he suffered in the sides' last encounter.

Boro return to Highbury again on Saturday in the fourth round of the FA Cup before the secong leg of the Carling semi at the Riverside a week tomorrow rounds off four meetings between the teams in the space of 18 days.

McClaren has already admitted that Southgate only has a "50-50'' chance of being fit for the next two games.

"I'm worried about him missing all three of these games against Arsenal,'' said McClaren. "He's doubtful, only 50-50.''

The Boro boss must patch up his rearguard and reaffirmed he is toying with the idea of drafting Mills and fellow full-back Franck Queudrue into central defence, possibly as part of a three-man formation.

Centre-back Chris Riggott is certain to figure, with Stuart Parnaby and Andrew Davies also in contention.

Wenger insisted after the last meeting that Henry would be rested for both Carling games, even though his side are desperately short of front players.

Dennis Bergkamp, Sylvain Wiltord and Jeremie Aliadiere are injured, but Kanu will play before linking up with Nigeria for the African Nations Cup.

But McClaren said: "I'm really not bothered about their team. It doesn't matter what team they put out, we know they have quality.

"I don't think there's any element of fear on our part, because everybody has written us off already.

"Everybody expects Arsenal to walk all over us, so we have nothing to lose and can have a real go.

"But we have to make sure we still have a good opportunity in the second leg - that's the objective.

"Arsenal are on a roll and they could go a full season unbeaten in the Premiership.

"They are the best team in the League at the moment and, after we've played them five times in all this season -possibly six if there's a replay in the FA Cup - the rest should be a damn sight easier.''

McClaren complained that the build-up to the game had been "low-key''.

He said: "There's not the sense of excitement there should be. Maybe people think it's a foregone conclusion that Arsenal are going to the final after the result the other week.''

Midfielder Gaizka Mendieta is set to return to Boro's starting line-up after fully recovering from a virus.

Meanwhile, McClaren insists he is "not interested'' in Manchester United striker Diego Forlan.

United will listen to offers for the Uruguayan now that they have lined up a £12m deal for Fulham's Louis Saha.

Forlan snubbed Boro two years ago when he joined United in a £7.5m deal after agreeing in principle to move to Teesside.

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