Former England skipper Lewis Moody believes Billy Vunipola's decision to swap London Wasps for Saracens is motivated by rugby reasons rather than money.

The 20-year-old, who has been recognised internationally by England boss Stuart Lancaster for the first time for next month’s Six Nations, will team up with brother Mako at Saracens in the summer.

Vunipola, who has played more than 30 times for London Wasps, has been a revelation this season – catching the eye of many Aviva Premiership admirers with a string of lung-busting performances.

After a catalogue of high-profile retirements at London Wasps in the last 18 months, including internationals such as Steve Thompson, Richard Birkett, Tom Rees, Joe Worsley, Dan Ward-Smith and John Hart – Vunipola has got his chance at Wycombe and he’s certainly grabbed it with both hands.

But it’s the opportunity to play alongside his brother Mako – himself now an England international – in a Saracens-side challenging on domestic and European fronts that appeals to Vunipola.

“Regardless of the money, Billy will now be playing in a side that are virtually guaranteed to be in the top four every season,” said Moody, who is an LV= Cup ambassador.

“If you look at the strength in depth Saracens have in their squad, it’s absolutely no surprise that they are going well in every competition they play in.

“And Billy will be joining that team, making it even stronger and in terms of furthering his international ambitions this can only help him.

“He will be playing in massive games week-in-week-out, something that Wasps could not guarantee him and I'm sure it will not be long before he is challenging consistently for international honours.”

London Wasps’ boss Dai Young has been desperate to tie the destructive backrow forward to a new long-term contract at the Buckinghamshire-based club and a sizeable offer had been put to Vunipola.

But Vunipola, who is the son of Fe'ao, who won 32 caps for Tonga and cousin of Welsh international Toby Faletau, turned down the lucrative offer and will now compete for a place next season in a star-studded Saracens’ backrow.

The news will come as a huge blow to Wasps, who in recent seasons have seen a host of international names depart the club in search of bigger deals and more international recognition.

“From what I understand Wasps had a sizeable offer on the table for Billy so it was not like money was ever an issue,” added Moody.

“He wanted to be playing with rather than against his brother Mako and quite frankly who can blame him?

“Wasps will obviously be disappointed, that’s to be expected, but at the end of the day that was what the player chose.”

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