HARLEQUINS put a huge dent in Saracens' Premiership play-off ambitions with a deserved 6-15 victory at Vicarage Road this evening.

Men in Black boss Alan Gaffney said his stuttering side's chances of securing a top four finish would hang in the balance if they slipped up, but the way they went down with a whimper will be of greater concern.

The hosts trailed 3-15 at the break after Quins made the most of the two opportunities that came their way, sandwiched between a disallowed Chris Jack effort for Sarries.

Danny Care put in flanker Chris Robshaw for their first try after 25 minutes before the influential scrum-half handed Ugo Monye the easiest of scores after picking out the wing in space with a delicate chip.

Fly-half Adrian Jarvis added a conversion to his earlier penalty after Gordon Ross, a late replacement for the injured Glen Jackson, had kicked Sarries into an early lead.

Ross added another three points in the second half but the result never looked in doubt as Quins controlled most of the play.

Sarries suffered a double blow before kick off with fly half Jackson forced out with an ankle injury and Tom Ryder succumbing to illness. Ross and Iain Fullarton were thrust into the first team with Hugh Vyvyan and Dan Scarbrough called up to the bench.

Ross, making his first start since the home defeat to Newcastle last December, kicked Sarries ahead after five minutes before Richard Haughton's half break in midfield was taken on by the supporting backs. However, Sarries were stopped short just a metre from the line before a knock-on handed the visitors possession.

Quins wing Tom Williams was almost put in from a chip to the right corner minutes later, but the bounce got the better of him as the frenetic start to the game showed no signs of letting up.

Then, from Williams' probing touch finder Sarries made a hash of their own line-out, allowing Quins to sweep the ball left before Rodd Penney intercepted, but the outside centre failed to keep hold of the ball.

Jarvis levelled up the scores with a shaky first penalty that bounced the right side off the left upright.

After 25 minutes, Quins made the breakthrough. Tani Fuga's line-out delivery at the Sarries 22 line was caught at the tail by James Percival and his instant off-load was taken by the onrushing Care. The 21-year-old raced through a gap before passing inside for flanker Robshaw to crash over. Jarvis pulled his conversion to the left of the posts.

Sarries responded immediately through Cencus Johnston's trunding break on halfway. Francisco Leonelli spotted Chris Jack hugging the left touchline and flighted a fine chip to the corner. The former All Black gathered gracefully, exchanged passes with Penney before touching down in the left corner.

However, TV replays showed the towering lock's momentum had pulled him into touch before he grounded the ball.

To add insult to injury, Quins raced up the other end and extended their lead further after 32 minutes, with Care again the architect.

After Will Skinner had gathered his own chip, Care booted a cross-field kick to the left corner where the unmarked Monye had all the time and space in the world to pick his spot under the posts. Jarvis added the extras for 3-15.

Leonelli picked up an injury and made way for late call up Scarbrough, the wing making his first senior Sarries appearance since damaging his knee against Gloucester at the start of the season.

The heavens opened at the interval, making playing conditions treacherous and prone to mistakes.

Ironically, it was referee Spreadbury who was guilty of making the first glaring error when he adjudged Ross's deep kick had bounced out of touch despite replays showing the ball was still in field.

The Men in Black upped the ante during the restart but could not find a way past the resolute Quins defence who were putting in plenty of secondary hits to stifle the hosts.

Ross landed his second three pointer 10 minutes in but failed to find the target eight minutes later.

With 20 minutes left Sarries desperately needed to pull something out of the hat and boss Alan Gaffney promptly threw on number eight Ben Skirving and new father Hugh Vyvyan, shortly followed by hooker Andy Kyriacou.

For several minutes Quins hemmed Sarries in their own 22 through a combination of fierce tackles and neat work at the breakdown.

Ross summed up his own display with a dreadful forward pass when a clearance kick was the obvious option with the game nearing an end.

Sarries looked nervous and at times desperate as they bumbled their way into opposition territory.

With four minutes left Quins replacement Chris Hala'ufia was sent to the cooler for a high tackle, but Ross missed a second successive penalty as the chance of a losing bonus point slipped away.

Gaffney made a triple change with Alan Dickens, Tom Mercey and Edd Thrower entering the fray, but it was too little, too late as Sarries exited the field to a chorus of boos.

Saracens: Russell, Haughton, Penney, Powell, Leonelli, Ross, de Kock (cpt); Lloyd, Ongaro, Johnston, Jack, Fullarton, Chesney, Hill, Gustard.

Replacements: Scarbrough for Leonelli, 32; Skirving for Chesney, Vyvyan for Fullarton, 61; Kyriacou for Ongaro, 64; Mercey for Johnston, Dickens for de Kock, Thrower for Russell, 78.

Referee: Tony Spreadbury.

Attendance: 6,553.

Scoring sequence: 3-0/3-3/3-8/3-13/3-15 HT/6-15.