Dundee United emerged from a game they did not want to play with an emphatic victory, but there was plenty of controversy as eight-man Hearts lost their sixth consecutive Clydesdale Bank Premier League game.

Barry Robson struck a hat-trick, consisting of two penalties and a free-kick which was heavily disputed after being given by referee Alan Freeland for a back pass.

Christophe Berra had levelled that opening goal just before the break but Hearts lost their discipline in the second period and had Marius Zaliukas, Lee Wallace and Michael Stewart sent off.

Dundee United had asked for the game to be postponed after the trauma of their match at Motherwell which saw the death of Phil O'Donnell after he collapsed on the pitch.

But the Scottish Premier League insisted the game went ahead with a pre-match tribute of a minute's applause for the Well skipper.

The game started quietly but it did not take long for controversy and hostility to break out in one of the most contentious games of the season.

Former Gretna left-back Danny Grainger survived a penalty appeal 10 minutes into his United debut when Freeland ruled his challenge on Calum Elliot was fair.

Grainger was one of three newcomers in the United squad but former Berwick midfielder Danny Swanson and on-loan Leicester forward Eric Odhiambo had to settle for places on the bench as Craig Levein recalled David Robertson.

Stephen Frail, Hearts' new caretaker boss recalled the fit-again Andrius Velicka and Saulius Mikoliunas with the injured Ibrahim Tall missing out along with Kestutis Ivaskevicius.

The atmosphere began to turn hostile as Robson was booked for a reckless challenge that left Elliot hobbling, while Grainger escaped similar punishment for a foul on Mikoliunas.

And Freeland further enraged the visiting fans by ruling that Robbie Neilson's miscue, which Banks caught, was a deliberate pass-back and awarded United a free-kick six yards from goal.

Velicka was booked for his part in the protests and the hosts took full advantage as Robson smashed the ball into the top corner following Lee Wilkie's touch back to give them a 23rd-minute lead.

Hearts' problems grew when Andrew Driver immediately hobbled off after appearing to injure his foot while slicing wide following a set-piece 20 yards out.

Deividas Cesnauskis replaced him to make his first club appearance since November 2006 following a series of injury problems.

But Hearts levelled in the 37th minute when Berra slid in to convert a Stewart corner that had been headed on by Zaliukas.

Morgaro Gomis was booked for a late tackle on Neilson before Robson missed a glorious chance.

The Scotland international, the subject of lingering speculation over a move to Celtic, could not connect properly in the six-yard box after Darren Dods had headed down Willo Flood's corner.

Swanson was introduced for David Robertson on the hour mark shortly before the hostility spread to Tynecastle infighting - Stewart and Berra squaring up to each other after Noel Hunt had been allowed space to shoot just wide from 12 yards.

And the controversy notched up another gear with red card and penalty for United.

Zaliukas elbowed Lee Wilkie off the ball in the penalty box after Hearts had cleared an attack and the Lithuanian was immediately sent off before Freeland, after a long delay and discussions with his assistant, pointed to the spot.

Neilson had been waiting to take a throw-in following the red card but the officials decided the incident had occurred when the ball was in play and Robson converted his second gift of the day in the 69th minute.

Swanson threatened twice from long distance and Robson shot straight at Banks from 25 yards, while Hearts almost lost another man when Stewart spoke out of turn after being booked for a foul on Robson.

Freeland let him off with a lecture but Hearts were finished off from the free-kick as Hunt exposed their offside trap to glance home Robson's delivery in the 84th minute.

And Lee Wallace followed Zaliukas down the tunnel when he brought down Robson inside the box after the United skipper had knocked the ball past the full-back.

Robson sent Banks the wrong way to complete his treble with three minutes left.

There was still time for Michal Pospisil to earn a yellow card and Odhiambo to make his debut and a game that began in sombre mood ended in even more controversy.

Stewart received a second yellow card in the closing seconds after Freeland's assistant alerted the referee to his touchline argument with a Hearts supporter in the stand.

Teams

Dundee Utd Szamotulski, Dillon, Wilkie (Kenneth 90), Dods,Grainger, Flood (Odhiambo 89), Kerr, Gomis, Robson,David Robertson (Swanson 60), Hunt.

Subs Not Used: McLean, Conway, Buaben, Jordan Robertson.

Booked: Robson, Gomis.

Goals: Robson 23, 70 pen, Hunt 84, Robson 88 pen.

Hearts Banks, Neilson, Zaliukas, Berra, Wallace,Mikoliunas (Pospisil 81), Stewart, Palazuelos,Driver (Cesnauskis 34), Velicka, Elliot (Nade 63).

Subs Not Used: Basso, Goncalves, Jonsson, McGowan.

Sent Off: Zaliukas (70), Wallace (87), Stewart (90).

Booked: Velicka, Stewart, Pospisil.

Goals: Berra 37.

Att: 12,100

Ref: A Freeland (Scotland).