Saracens' stars beat a spirited and largely homegrown London Irish side to register their 12th win of the season.

Billy Vunipola put Saracens further ahead before Matt Williams responded, but George added his second try just before half-time.

Richard Barrington went over twice after the restart before Williams had a late try disallowed for Irish.

Saracens, penalised for salary cap breaches, remain bottom but are now on minus 47 points while Irish stay in ninth place, seven points below eighth-placed Gloucester.

Having already been relegated, Saracens had one eye on their Champions Cup quarter-final with Leinster in mid-September, and while their largely first-choice line-up - minus Owen Farrell and Mako Vunipola - were never in trouble, an inexperienced Irish side ensured they did not have it all their own way.

London Irish, with nine starters who had come through their academy, started brightly and but for a poor pass by Curtis Rona could have been first on the scoreboard when he missed Ross Neal with a two-on-one chance on the right wing.

The reigning champions quickly got into their stride as George was mauled over after 10 minutes from a five-metre line-out, with Barritt scoring by the same method three minutes later.

Irish did not crumble and a good period of play was rewarded when Pumas hooker Creevy grabbed a debut try midway through the first half, but five minutes later Vunipola scored from close range after a quick free-kick for his side's third try.

The Exiles continued to threaten and Williams was on hand to convert after Vunipola and his England colleague Maro Itoje were involved in a mix-up inside their own 22, but George restored the two-try advantage with another push-over touchdown from another five-metre line-out after 33 minutes.

Barrington twice forced his way over in a three-minute spell with half an hour to go as Saracens pounced on the hosts' mistakes, while Juan Pablo Socino had his first try for the club ruled out by a television replay with 10 minutes left after a forward pass from Sean Maitland.

Irish thought they had a third try inside the final three minutes as Williams raced through after a Saracens knock-on, but video replays showed the centre had knocked it on himself.

Only leaders Exeter Chiefs have won more league games than Saracens this season.

London Irish: Parton; Stokes, Rona, Williams, Neal; Atkins, Brand; Goodrick-Clarke, Creevy, Chawatama, Donnell, Munga, Cooke, Curtis-Harris, Rogerson (capt).

Replacements: Cornish, Dell, Hoskins, De Chaves, Ioane, Englefield, Cokanasiga, Norton.

Saracens: Goode; Lewington, Daly, Barritt (capt), Maitland; M Vunipola, Davies; Barrington, George, Koch, Itoje, Hunter-Hill, Rhodes, Wray, B Vunipola.

Replacements: Woolstencroft, Crean, Ibuanokpe, Kpoku, Clark, Whiteley, Socino, Morris.

Referee: Tom Foley.