Manu Vunipola’s nerveless late penalty handed reigning champions Saracens a dramatic win over valiant newly-promoted London Irish at Allianz Park.

Ham & High: Saracens' players celebrate after Titi Lamositele drives over to score a try during the Gallagher Premiership match at the Allianz Stadium, London.Saracens' players celebrate after Titi Lamositele drives over to score a try during the Gallagher Premiership match at the Allianz Stadium, London. (Image: PA Wire/PA Images)

Vunipola's cousins Billy and Mako may have suffered defeat in the World Cup final earlier in the day but the young fly-half ensured that the family would at least have something to celebrate as he put a patchy performance from the tee behind him to slot the decisive three-pointer.

That came only a couple of minutes after Ben Earl had crossed to draw Saracens level and while Vunipola missed the conversion, he soon earned redemption and broke Irish hearts.

The Exiles had built a 13-8 lead when Albert Tuisue ploughed over 10 minutes into the second half, but the visitors had to settle for just a losing bonus point.

London Irish started the brighter and looked like they had scored a try within two minutes when Ruan Botha finished off a powerful drive. However, it was disallowed for double movement.

Ham & High: Saracens' Alex Lozowski kicks a penalty during the Gallagher Premiership match at the Allianz Stadium, London.Saracens' Alex Lozowski kicks a penalty during the Gallagher Premiership match at the Allianz Stadium, London. (Image: PA Wire/PA Images)

Stephen Myler gave the visitors the lead with a penalty after nine minutes, but this was cancelled out five minutes later by Alex Lozowski.

The first half was full of end-to-end action and, in the 26th minute, Saracens scored the opening try. A rolling maul by the hosts enabled Titi Lamositele to score and give them the lead.

Saracens failed to convert and then saw their lead cut five minutes later with Myler's second penalty of the afternoon.

Already bad conditions worsened after the break as both sides found handling and kicking complicated in driving rain and temperamental winds.

Ham & High: Saracens' Duncan Taylor is tackled by London Irish's Tom Stephenson (left) during the Gallagher Premiership match at the Allianz Stadium, London.Saracens' Duncan Taylor is tackled by London Irish's Tom Stephenson (left) during the Gallagher Premiership match at the Allianz Stadium, London. (Image: PA Wire/PA Images)

In the 56th minute, lots of pressure from London Irish close to the try line finally paid off as Tuisue scored following a rolling maul. Myler's conversion was good, giving the Exiles a five-point lead.

Sarries took their time to respond to London Irish's resilience in only their third match back in English rugby's top tier but they finally made the breakthrough with three minutes to go.

Another rolling maul led to a try for Earl - his third in two games - although the conversion was missed twice by Vunipola, as it was ordered to be retaken following encroachment from London Irish.

The match looked all set for a draw until Sarries were awarded a penalty and, as the clocked ticked down, Vunipola kept his nerve to slot the decisive kick.

Ham & High: Saracens' Matt Gallagher (right) attempts to claim a high ball ahead of London Irish's Curtis Rona during the Gallagher Premiership match at the Allianz Stadium, London.Saracens' Matt Gallagher (right) attempts to claim a high ball ahead of London Irish's Curtis Rona during the Gallagher Premiership match at the Allianz Stadium, London. (Image: PA Wire/PA Images)

Saracens can now welcome back a slew of first-team players from the World Cup with two wins from three under their belts in the league.

Ham & High: Saracens' Richard Wigglesworth prepares to put the ball into a scrum during the Gallagher Premiership match at the Allianz Stadium, London.Saracens' Richard Wigglesworth prepares to put the ball into a scrum during the Gallagher Premiership match at the Allianz Stadium, London. (Image: PA Wire/PA Images)