Fit and leaner Vunipola has stomach for England call ROOKIE Saracens prop Mako Vunipola has been fast-tracked into the England squad for the QBE autumn internationals after ditching the fast food. Vunipola, the 20-stone loosehead of Tongan descent, has only made four Aviva Premiership starts for Saracens and one in the Heineken Cup. However, with Alex Corbisiero still recovering from a knee injury, England forwards coach Graham Rowntree felt Vunipola's form was simply too good to ignore. The 21-year-old will go straight into England's matchday squad for the Tests against Fiji, Australia, South Africa and New Zealand. I have no doubt he will make his name in this autumn series. I have got every confidence in him," Rowntree said. I am looking for a fault in his game and I can't find one at the moment. He has got himself fit. His form has been exceptional. I like his commitment to every aspect of the game. He is a dynamic ball-carrier and he loves a scrum. He respects all the hard yards, the tackling, the clearing out, the scrummaging. He has got his priorities right. That has not always been the case. There was a time, during his days at Millfield and in England's age-grade teams, when Vunipola's appetite for rugby was only exceeded by his appetite. The action photos of Vunipola, in his tight England under-20s jersey at last year's Junior World Championships, are not flattering. By his own admission, when Vunipola joined Saracens from Bristol in the summer of 2011 he was "not in great shape" and he found the transition to professionalism a culture shock. Vunipola spent most of last season sidelined with foot and hamstring injuries but that time out allowed Saracens" fitness coaches to get hold of him. "Mako brings something different to the party," said England coach Andy Farrell, who coached Vunipola at Saracens. He turned professional 18 months ago when he came to Saracens and that took its toll on his body straight away. It is not easy, especially as a front-row forward, to cope with the demands of the Premiership but he has got his body in such a condition now that he is playing exceptionally well. His form this year has been down to a change of attitude. He has grown up a lot over the last six months. He has got stuck into his living outside of rugby, his fitness, his training is second to none. Vunipola was born in Wellington, New Zealand. His father, Fe'ao, won 32 caps for Tonga and played at the 1995 and 1999 World Cups. The family relocated to Wales when Fe'ao signed for Pontypool in 1998 and Vunipola qualifies for the Grand Slam champions. But Vunipola - like his brother Billy, the Wasps forward - has always nailed his international colours to England's mast, having worn the rose at under-18 and under-20 level. "Mako is as good a rugby-playing loosehead as I have come across," Saracens director of rugby Mark McCall said. He has played some big games for us and is an outstanding talent. Vunipola is one of four injury-enforced changes England have made to their squad for the autumn Tests. The uncapped Leicester hooker Tom Youngs will be Dylan Hartley's understudy after making a big impression on Rowntree during the summer tour of South Africa. Harlequins wing Ugo Monye and Wasps flanker James Haskell have both been recalled, replacing Ben Foden and Tom Croft respectively. Monye's last England appearance was against Scotland in 2010, when he was carried off at Murrayfield with a neck injury, but he has scored five Premiership tries already this season.