With his current deal expiring at the end of the season, the 24-year old has put pen to paper on a new contract that runs until the end of the 2015/16 campaign.
Bridgend born Webb is a product of the Ospreys development pathway, coming through the age-grade ranks at the region before signing his first development contract ahead of the 2007/08 season.
His senior debut was as a 19-year old, coming off the bench during a 32-7 win over Ulster at the Liberty Stadium during March 2008, with his first start coming two months later in an 18-10 defeat at Newport Gwent Dragons. To date he has 87 Ospreys appearances to his name and has scored seven tries.
Capped by Wales at age-grade level, he made his senior international debut during last season's Grand Slam campaign in the win over Italy at the Millennium Stadium before adding a further two caps last June, against Barbarians and in the second test against Australia. He was also a member of the Welsh squad that won the Sevens World Cup in Dubai in 2009.
Speaking after signing his new deal, Webb commented:
"I'm absolutely thrilled. To be able to commit to another three years with my home region is fantastic. It's a brilliant environment here, the only place I want to play rugby.
"Having done so well last season I've obviously been disappointed to not get so much game time this year, but I've had to knuckle down and work hard. Kahn has been a great help for me in terms of development and I believe that if I keep on working hard I can become a much better player over the three years of my new contract.
"I take great pride in wearing the Ospreys shirt. We've got a good, young group of players together here that can serve the region well for a long time and I'm pleased that I can be a part of it."
Andy Lloyd, Rugby Operations Manager at the Ospreys, said:
"It's great news for Rhys and for the region. It's important that we keep hold of young, talented home grown players who have already shown that they can compete at the top level and he certainly fits that description.
"He's been unfortunate in the amount of game time he's had this season due to the form of others in the squad, but we saw last season what he is capable of when he was one of the form scrum halves in Wales. He thoroughly deserved his place in the starting line-up for the PRO12 Final in Dublin and on the Wales tour to Australia.
"He is only going to get better over the course of this contract. He's a fantastic athlete and is totally committed to the Ospreys cause, coming from one of the hotbeds of the region in Bridgend, and we are delighted to have him on board for the next three years.
"With the addition of Tito Tebaldi confirmed for next season, someone of Rhys' proven ability signing a new contract, and then with the potential of Tom Habberfield, it bodes well for the Ospreys. Ideally, we would want to go into a season with as many as five scrum halves available to cover injury and potential international recognition, but the reality of the salary cap is that we have to go with three for next season."
Webb follows on from Joe Bearman in recommitting to the Ospreys this week, while young forwards James King and Lloyd Peers signed new deals at the end of December.
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