Spinner Adam Riley says he is pleased to put a frustrating 2015 season behind him and sign a contract extension at Kent.

Despite a breakthrough 2014 campaign seeing him usurp James Tredwell as Kent's premier slow bowler and claim 57 First Class wickets and earn an England Lions call-up, the 23-year-old off-spinner was limited to just eight appearances in LV=County Championship Division 2 as he struggled for form this summer.

He did finish the season with 4-47 in the huge win at Glamorgan last month, but Riley claimed just eight red-ball scalps in-all in 2015, at an average of 53, and four in five T20 appearances, costing 30.75 apiece.

Riley revealed: "I always wanted to commit my future to Kent. It has dragged on a bit due to some outside influences but I am pleased to have signed.

"2015 was a pretty frustrating season for me, with how it played out after my success of the year before, but it has made me even more determined to show what I am capable of."

Asked about the reason for his downturn in fortunes this term, Riley spoke frankly, admitting: "I was in and out of the side because my form was not very good through the season.

"I don't think it was second season syndrome, or anyone knowing more about me this year, I was not in good enough form in June and they brought Treddy back in.

"One crumb of comfort was that I went away and worked on a few things, made some subtle changes, I battled on and got back into the team late in the season and got some wickets at Glamorgan.

"Hopefully I can kick-on from there, put some good work in over the winter ready to hit the ground running in 2016."

Sidcup-born Riley has 143 wickets in 100 first-team appearances since his debut in 2011 and he added: "Kent have given me plenty of opportunity since I signed my first contract so I am delighted that I can continue my development here - my home county.

“With Sam Northeast taking over as skipper and so many of our other key players also committing their futures, all signs suggest that we are a county heading in the right direction.

“The squad is very excited to see what we can achieve next year. We finished the season strongly in Championship cricket and we will be aiming to go even further in the limited-overs competitions in 2016."

Kent Chairman of cricket Graham Johnson said: “It’s great to see another young Kent player commit his future to the club and keep our core of home-grown talent together.

“Adam has all the tools to become an international spinner and we hope the environment at Kent is the perfect place to help him realise that aim. He has also demonstrated that he can offer much more than just his bowling to Kent in the future.

“2015 was a frustrating year for Adam but it does not diminish, in the slightest, our belief that Adam can reach his full potential.

“Along with James Tredwell, the promising Imran Qayyum and the likes of Fabian Cowdrey and Joe Denly, Kent have a pool of spin talent to handle the varied demands of T20, one-day and four-day cricket.”