Aberdeen striker Sam Cosgrove turns from saint to sinner: he's booked for a raised arm in an aerial challenge on Borna Barisic.

Moments later, Aberdeen captain Graeme Shinnie is booked for a late challenge on Scott Arfield, sparking a melee or stramash involving more than a few players from both sides.

Referee Kevin Clancy does well to restore claim.

Former Rangers midfielder Neil McCann on Sportsound: "I just don't understand how Considine misses it. It's gift-wrapped. There's enough pace on the cross, he doesn't have to generate any power. Just go and put the meat on it and get it on target and your side's 2-1 up. He gets it all wrong."

Aberdeen's aerial bombardment of Allan McGregor's goal continues but Scott McKenna's header fails to find the target.

With 25 to go, who's going to win this one? Or are we destined for a replay on 12 March?

Former Aberdeen defender Willie Miller on Sportsound: "Andy Considine is totally free, six yards out. All he has to do is get it on target and it's in the net. It's such a bad header by Considine.

How on earth did that stay out? Niall McGinn's corner causes fear and alarm in the Rangers penalty area - Andrew Considine flies through the air... but fails to connect!

Scott McKenna sends the ball back in, Sam Cosgrove sees his effort blocked and Rangers clear.

"Chances don't come much better than that," says BBC Sportsound pundit Neil McCann.

Rangers could and perhaps should be ahead. Scott Arfield, teed up by Ryan Kent, sees his attempted chip clear Joe Lewis and the crossbar.

The visitors are warming to the task in this fascinating quarter-final tie...

Former Aberdeen defender Willie Miller on Sportsound: For me there is contact on Connor McLennan, Joe Worrall definitely throws a leg out and he's nowhere near the ball. Maybe the referee thought he made too much of it. On this occasion there's no penalty but there could have easily been one.

Dundee United: Siegrist, Connolly, Reynolds, Seaman, Robson, Fyvie, C.Smith, Harkes, Pawlett, Clark, Safranko.

Substitutes: Laidlaw, Booth, McMullan, Stanton, Gomis, Nesbitt, Watson.

Inverness CT: Ridgers, McKay, Donaldson, McCart, Tremarco, Trafford, Chalmers, Welsh, Polworth, Doran, White.

Substitutes: C.Mackay, Rooney, McCauley, Austin, D.Mackay, MacGregor, Hyde.

BBC Scotland's Tyrone Smith at Pittodrie: "So far in this second half, Rangers have been everything that Aberdeen were in the first..."

A second booking for simulation at Pittodrie as Connor McLennan tumbles in the box close to Rangers defender Joe Worrall.

Referee Kevin Clancy trots over to brandish the yellow - didn't look like any contact there.

BBC Sportsound pundit Willier Miller: "It's been a great start for Rangers getting the equaliser - which should have been defended better - and this cup tie is finely poised."

Image source, SNS

Alfredo Morelos has cut a frustrated figure for Rangers this afternoon. The Colombian's cup tie is offering little in the way of cheer after the break as he appears to be fouled by Andrew Considine but referee Kevin Clancy is having none of it.

Morelos beats the turf in frustration.

We're back under way at Pittodrie

Rangers goalkeeper Allan McGregor got a hand to Sam Cosgrove's penalty but couldn't prevent Aberdeen taking the lead.

Image source, PA

Our player rater is up and running, so you can cast your marks out of 10 for the men in action at Pittodrie. Who has impressed you so far?

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Former Rangers midfielder Neil McCann on BBC Sportsound: "Fair play to Derek McInnes, it's not the obvious choice to play Connor McLennan through the middle but it's worked.

"For Rangers, they need to mix it up a little bit, go a little bit longer. They've got the pace in Ryan Kent, make it a foot race and force Aberdeen to go deeper."

Image source, SNS

Former Aberdeen defender Willie Miller on Sportsound: Aberdeen have battled well and they deserve their lead at half-time. They haven't allowed Rangers any space in the midfield, who I think have been overrun. You have to put the penalty down to an error by Connor Goldson, it was good work by Gary Mackay-Steven to get in behind but bad defending by Goldson.