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Middleton bends terrific strike into far corner on his first Utd start for deserved lead
Birighitti denies AZ striker Pavlidis with sprawling save late on
Sides meet again in the Netherlands next Thursday
Dundee United 0-0 AZ Alkmaar
Craig Levein
Former Scotland manager on BBC Sportsound
Quote MessageUnited have slowly been coming into the game. They started on the back foot and gave away a lot of possession but they're getting into it now.
Dundee Utd 0-0 AZ Alkmaar
What a noise.
Craig Sibbald takes a brilliant first touch and leathers one from the left of the box.
AZ keeper Verhulst is across to get strong hands on it.
Dundee Utd 0-0 AZ Alkmaar
Ian Harkes plucks a Ryan Edwards ball out of orbit. Brilliant control.
The American can't win a corner, though, as United keep forcing the issue.
Dundee Utd 0-0 AZ Alkmaar
United are settling into this.
This is far more encouraging and the crowd are with them every step of the way.
Dundee United 0-0 AZ Alkmaar
Craig Levein
Former Scotland manager on BBC Sportsound
Quote MessageIt takes two or three committed tackles like that and this place goes up levels. Ryan Edwards' tackle there did that.
Dundee Utd 0-0 AZ Alkmaar
Finally a bit of stable possession for United as Kieran Freeman's cross is hacked away.
Ryan Edwards then crunches into a fine tackle, prompting a huge roar from the home support.
That's more like it.
Dundee United 0-0 AZ Alkmaar
James McFadden
Former Scotland forward on BBC Scotland
Quote MessageMark Birighitti in the Dundee United goal is not rushing, which is good, but he is making mistakes on the ball. Two passes to his full-backs have caused Dundee United problems.
Dundee United 0-0 AZ Alkmaar
Craig Levein
Former Scotland manager on BBC Sportsound
Quote MessageFreeman is getting pulled inside and then at the last minute he'll dart around the outside. He's been caught on numerous occasions.
Dundee United 0-0 AZ Alkmaar
Been a bit of a dip in the atmosphere as AZ continue to dominate.
Really slack passes like the one we've just seen from home keeper Mark Birighitti won't help.
Dundee United 0-0 AZ Alkmaar
Craig Easton
Former Dundee Utd midfielder on BBC Sportsound
Quote MessageThat's an incredible let-off for United. They're lucky because it ricochets off Ryan Edwards, they've really got away with one there.
Dundee United 0-0 AZ Alkmaar
Scare for United as they give the ball away cheaply and a low cross into the box just hits Ryan Edwards.
The hosts then need to be on hand to deal with an AZ corner.
Dundee United 0-0 AZ Alkmaar
Could be a long night for United if they don't keep possession.
AZ again build an attack well but Glenn Middleton nips away with the ball. The hosts can't hold it, though.
Dundee United 0-0 AZ Alkmaar
Craig Easton
Former Dundee Utd midfielder on BBC Sportsound
Quote MessageDundee United are quite happy to afford AZ some possession, force them wide and wait to win it back again.
Dundee United 0-0 AZ Alkmaar
Another foul won by Tony Watt, this time deep in his own half.
He's excellent at buying free-kicks.
Dundee United 0-0 AZ Alkmaar
United try a pre-planned set-piece but it comes nothing.
AZ not shy when it comes to playing through a press.
Dundee United 0-0 AZ Alkmaar
A punt forward finds Tony Watt on the left, who has a cross blocked.
Watt picks the ball up again and wins a foul in a good position.
Dundee United 0-0 AZ Alkmaar
A minute in and you can already see AZ's class.
Just purely in the way the Dutch team are moving the ball here.
Dundee United 0-0 AZ Alkmaar
Aaaaand we're off.
Portuguese referee Vitor Ferreira gets us under way...
Image source, SNSHere come the players.
Eh, aye... it sounds loud there.
Dundee United v AZ Alkmaar (20:00)
Craig Easton
Former Dundee Utd midfielder on BBC Sportsound
Quote MessageI think the midfield three could be massive for United tonight. They all bring something different to the table.