London Irish recorded a fifth straight Guinness Premiership win as tries from Sailosi Tagicakibau and Gonzalo Tiesi saw the Exiles take another giant stride towards play-off qualification.

Despite the return to full fitness of Glen Jackson, Sarries slumped to a fifth loss in their last seven games as the fly-half missed a penalty in the final minute at the Madejski Stadium.

Saracens have now scored just eight tries in their last six games and with Irish number 15 Peter Hewat in fine form to rattle in 17 points, Ben Skirving and Kameli Ratuvou touchdowns were never going to be enough for the visitors.

After an opening five minutes dominated by Saracens, the mercurial Jackson kicked the first points in the seventh minute with a 30-metre penalty in front of the posts.

Irish, who controversially slumped against Sarries back in November, were in front by 14 minutes as two penalties from Hewat handed the Exiles the advantage.

Sarries were reduced to 14 men in the 26th minute when lock Kris Chesney was sin-binned for diving over at the breakdown.

Hewat kicked another penalty to take Irish six points clear only to be pegged back after Jackson slotted his second penalty in the 30th minute.

Irish doubled the lead three minutes later when Hewat kicked a penalty from 20 metres after Saracens second-rower Hugh Vyvyan was caught with his hands in the ruck.

But a Skirving try two minutes before the break was converted by Jackson, meaning Sarries took a one-point lead into the interval against the run of play.

Sarries top scorer Jackson extended his side's lead and his tally with another three points in the 49th minute after the New Zealander had missed a kick minutes earlier.

London Irish regained the lead in the 54th minute after winger Topsy Ojo broke through the Sarries back line. The former England Under-21 international slipped the ball to Tagicakibau and the 24-year-old went over for his first of the season.

Another breakaway try four minutes later from Tiesi kept the Exiles in front as they mounted yet more misery on Sarries.

Jackson reduced the deficit to five points when he converted another penalty as Sarries started a mini-revival.

But the home side fought back and Hewat extended Irish's lead in an economical kicking display taking his personal tally to 17 points.

Ratuvou went over for Sarries in the 74th minute but it proved too little too late for the out-of-form visitors as Jackson missed his kick late on.