Rangers offered the most resounding sign yet the Scottish Premier League title race may already have run its course with an emphatic victory at Dundee United.

Celtic lost at Tannadice back in August, but there were to be no mistakes from Rangers as they extended their lead at the summit to an imposing nine points.

Indeed the only errors on show came from United in what was a personal nightmare for home keeper Alan Combe who allowed Rangers almost identical first half goals from corners.

The first, on just eight minutes, was nodded in by Tony Vidmar, the second claimed by the same player but given as a David Partridge own goal - both via Giovanni Van Bronckhorst flag kicks.

With that advantage gained by the 23rd minute, Rangers were able to relax thereafter, but had the nous to halt a brief United flurry with a well worked Rod Wallace goal on 67 minutes.

To compound United's misery, substitute Neil McCann claimed a Rangers fourth with just five minutes remaining to outline the visitors' championship credentials.

United were without first-choice midfield duo Jan Telesnikov and Craig Easton through injury, while Rangers welcomed back Billy Dodds from suspension to face his former club.

Rangers were dominant from the outset and Vidmar had claims for a penalty rejected in the fourth minute when he claimed he was obstructed by Partridge.

The Australian defender was to fare better four minutes later as he headed in at the far post from close range after Alan Combe spilled a Van Bronckhorst corner.

It was a head start United could ill-afford to have conceded and though Bernard Pascual scooped the effort away from goal the ball was adjudged to have crossed the line.

United's response was immediate, a Siggi Jonsson free-kick beaten away by Stefan Klos and Jason De Vos dragging his shot well wide of the mark from the rebound.

Barry Ferguson spurned Rangers' next chance, feeding Arthur Numan on the left before sending a header off target as United again looked stretched at the back.

Combe looked to have redeemed himself after 22 minutes when he pushed away a powerful goalward bound angled drive from Van Bronckhorst - but it was not proving the keeper's night.

From the resulting corner, again taken by Van Bronckhorst, Combe was left standing as the ball cleared him and was bundled in at the far post.

The first indication was a second for Vidmar, but while he claimed the goal, television replays indicated the final touch had been from United defender Partridge.

Unhappy Paul Sturrock made a positive tactical switch on the half-hour as he withdrew Hugh Davidson, a midfielder, for another striker, in recent Aberdeen recruit Jim Hamilton.

Rangers were playing some fluid football and it needed a brave block from Tony Smith to deny Van Bronckhorst converting after Ferguson and Numan had combined well on the left.

United, who had effectively gifted Rangers their interval lead, opted to add the experienced Maurice Malpas as a second-half substitute for Smith.

The home team came close to pulling a goal back after 57 minutes when Pascual's cross from the left found the head of substitute Hamilton who forced Klos into a fine low save.

Rangers looked to have settled for what they had and their lethargy was almost punished by Jonsson after 63 minutes but he shot too close to keeper Klos.

United made a final switch after 62 minutes, introducing Joaquim Ferraz for Steven Thompson, but in Rangers' next attack the contest was put beyond doubt.

Rangers increased the tempo to telling effect as Numan drilled in a cross from the left which Wallace guided past Combe with a flicked header to leave United trailing 3-0.

United persisted manfully, Pascual delivering another precise cross this time for Ferraz to head wide, but the gap in class was always too much for them to overcome.

That was demonstrated again with five minutes remaining when a Numan cross struck Wallace and proved inviting for substitute Neil McCann to hook over Combe and in.

Rangers came close to a fifth through Jorg Albertz in the final minute, yet by then the damage had been done, not just to United, but to Celtic too.

Teams

Dundee Utd: Combe, Pascual, De Vos, Partridge, Skoldmark, Smith (Malpas 46), Hannah, Jonsson, Davidson (Hamilton 51), Mathie, Thompson (Ferraz 62).

Subs Not Used: Onstad, Venetis.

Booked: Combe, Jonsson.

Rangers: Klos, Numan, Vidmar, Amoruso, Moore, Albertz, Van Bronckhorst (Kerimoglu 80), Ferguson, Kanchelskis (Reyna 78), Wallace, Dodds (McCann 75).

Subs Not Used: Charbonnier, Nicholson.

Booked: Van Bronckhorst, Moore.

Goals: Vidmar 8, Partridge 22 og, Wallace 68, McCann 85.

Att: 11,241

Ref: Stuart Dougal (Scotland).