Dundee United stand on the brink of relegation from the cinch Premiership after Kyle Vassell's double sent Kilmarnock on their way to a 3-0 victory at Tannadice which keeps them in pole position in the battle for survival.

United suffered a fourth consecutive defeat which, coupled with Ross County's draw against St Johnstone, left them needing a hugely unlikely turn of events on the final day on Sunday to avoid a second relegation in seven years.

United need to beat in-form Motherwell at Fir Park and hope Killie beat Ross County and somehow engineer an eight-goal swing along the way.

Killie are three points ahead of County but will need to get at least a point against the Dingwall side on Sunday to stay out of the play-off spot.

United boss Jim Goodwin admitted after his side's third consecutive defeat on Saturday against Livingston that they "keep shooting ourselves in the foot" with defensive errors, and the two goals they conceded in the first half to Vassell were textbook examples.

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The home side went down with a whimper and Innes Cameron came off the bench to net a late third on the counter-attack.

Goodwin had made some major decisions in his team selection. Mark Birighitti was dropped after the goalkeeper's latest blunder in a difficult season and 21-year-old Jack Newman was handed his second start for the club. His first ended in a 4-0 defeat by Ross County. Steven Fletcher started after missing Saturday's game with a groin injury and Peter Pawlett made his fourth start of the season.

Defenders Chris Stokes and Ash Taylor returned from injury for Killie and, with David Watson and Liam Donnelly dropping out through suspension and injury respectively, Liam Polworth and Brad Lyons came into their midfield.

The opener came in the 14th minute after Loick Ayina tried to dribble past a third opponent on his way out of his own penalty box. The United centre-back overran the ball, lunged into a strong tackle which went unpunished by referee Alan Muir, but the ball was in the corner of the net two seconds later after ultimately falling for Vassell 18 yards out.

Vassell soon came close to an extraordinary second goal. The striker chested the ball down inside the centre circle with his back to goal and turned and lobbed Newman, who did well to backtrack and push the ball over his bar almost on the line.

The Northern Ireland international did net again in the 44th minute after more sloppy play in possession from the hosts.

Ilmari Niskanen played a slack pass towards Ayina, Christian Doidge won the ball and lifted it over Newman before being cleaned out by the goalkeeper. Vassell made sure there was no need for a penalty by knocking the ball home.

United were booed off at half-time after an unconvincing attacking display. Fletcher and Pawlett both fluffed good chances before being flagged offside anyway, and the former volleyed over first time.

Goodwin brought on Dylan Levitt and Glenn Middleton for the second half but there was little sign of improvement.

Vassell went off injured following a foul by Charlie Mulgrew but his replacement, Cameron, marked his return from nine months out with injury by converting following Rory McKenzie's break forward in the 83rd minute.

Rory McLeod hit the post for United before Sam Walker saved from another sub, Miller Thomson, but most of the home fans had already left.

A late goal for Ross County was set to put United down until former United player Ryan McGowan levelled for St Johnstone, but their fate is all but sealed.

What the managers said...

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Dundee United boss Jim Goodwin: "I came in and people thought I was mad, but I genuinely thought I could turn it around and we did get a bounce from the players.

"Unfortunately the defensive frailties reared their head again and ultimately that's what's cost us. It's one of the lowest points in my career.

"We will go to Motherwell on Sunday and give it our best shot. I am one of the biggest optimists out there so I will always try to be positive and believe the impossible can sometimes happen.

"But, of course, it's an eight-goal swing so we have to go to Motherwell and score a hell of a lot of goals then hope Kilmarnock hammer Ross County. The likelihood of that happening is obviously very slim.

"But at the same time we have to go to Motherwell and play for pride and try to earn back the respect of the fans.

"The fans have every right to show their emotions the way they did at the end. There isn't a player in there who can't accept their part in it. There are good, talented individuals within the squad.

"But as a team this season simply hasn't been good enough and I said that to them in the dressing room.

"As managers, myself, Jack Ross and Liam Fox we will take our share of the blame because we are in it together. As a team it hasn't been good enough and the league table doesn't lie."

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Kilmarnock boss Derek McInnes: "There is still work to do, nobody is over-celebrating or getting ahead of ourselves, but it's important we enjoy the moment.

"The supporters came up in huge numbers and it's great to send them home probably feeling a lot more optimistic.

"But we have still got a tough game to navigate, it's all or nothing. It is set up nicely for both teams and we have a job to do but what pleased me was the performance and our approach to the game.

"We were very confident, we asked the players to play with optimism and belief and we had that. We were aggressive with our work and imposed ourselves on the game and with the position Dundee United were in, getting that first goal was crucial.

"All week I have been getting asked about the pressure and anxiety of players and how we handle that and I thought the players dealt with the game really well."

What's next?

Dundee United's final game of the season is away to Motherwell on Sunday, while Kilmarnock host Ross County.

Both games kick-off at 12.30pm.

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