The 21-year-old attack-minded midfielder spent time with Thurlow Nunn League outfit Newmarket Town as a youngster before joining Cambridge United's scholarship programme in 2016.

He signed a professional development contract at the beginning of the 2017/18 season and recently signed a new contract until 2020/21.

During his time with the U's, Knowles has spent time out on loan with BetVictor Southern League outfits St Neots Town, St Ives Town and Royston Town, now-Isthmian League North Cambridge City, as well as league rivals Dartford and Hemel Hempstead Town and National League North side Kettering Town.

He has also made appearances for Cambridge United's first team with his opportunities coming towards the end of last season, scoring his first goal in a home fixture against Morecambe.

Meanwhile, defender Chris Gregan has extended his stay with BetVictor Isthmian League Premier Division side Bishop's Stortford.

The left-back joined Stortford last month on an initial one-month loan and has extended his stay for a further month, with the option for an immediate recall.

So far Gregan has made 4 appearances for the Blues.