Jennings began his career with his hometown club Stockport County and joined Wigan Athletic in 2012. He went on loan at Accrington Stanley in March 2015 but failed to make an appearance for Stanley through injury. He made his professional debut on 11 August 2015 in a 2–1 League Cup defeat against Bury. On 12 November 2015, Jennings joined National League side Cheltenham Town on an initial one-month loan deal.

In February 2016, Jennings joined National League side Grimsby Town on loan until the end of the season. Ryan was part of the team that eventually went on to beat Forest Green Rovers 3–1 in the 2016 National League play-off Final at Wembley, seeing Grimsby promoted to League Two after a six-year absence from the Football League.

In September 2016 Jennings joined National League North side Fylde, but by December he had joined local league rivals Curzon Ashton. Ryan played against the Boro' last season whilst with Alfreton Town.

November 2018

Sat, 17 November

Alfreton Town

Nuneaton Borough 1st Team

The Vanarama National League - Vanarama National League North

Sub On (58’)

Tue, 20 November

Nuneaton Borough 1st Team

Solihull Moors

Cup

Sub Off (69’)

Sat, 24 November