His playing time there was limited, so to gain first-team experience Liverpool loaned him out to Scunthorpe United and Leicester City.

At 16 years and 149 days, he became the club's youngest ever debutant, breaking a record that was previously held by Shane Nicholson.

[14] He made his first start for Liverpool against Cardiff City in the League Cup on 31 October, playing all 90 minutes, and gaining praise from pundits and teammates for his composed performance.

[15] On 2 December, Hobbs made his league debut against Bolton Wanderers, replacing Jamie Carragher in the 51st minute of a 4–0 home win.

[18] He scored the first goal of his career on 15 February with a header from Ian Morris' cross in the 23rd minute of a 3–2 defeat away to Stoke City.

[24][25] Hobbs scored his first goal on 24 January 2009, with a header from Steve Howard's flick-on in a 4–2 victory over Huddersfield Town.

[28] In his first season with the club, besides winning the League One title and achieving promotion to the Championship, Hobbs was also included in the PFA Team of the Year.

[32] Playing alongside Wayne Brown at centre-back, Hobbs missed only two league matches in the 2009–10 season,[33] and made a total of 49 appearances.

With speculation that Leicester would sign Chelsea defender Jeffrey Bruma on loan, new manager Sven-Göran Eriksson said that Hobbs could join another club.

[35] Failing to break into the team due to competition from James Chester and Anthony Gerrard, Hobbs expressed his desire to return to Leicester once the loan spell ended.

[42] On 11 February 2012, he scored his first league goal in three years in a 3–0 home victory over Bristol City, heading in a Robert Koren cross.

[43] During a match against Coventry City on 31 March, he injured himself while tackling Alex Nimely during first-half stoppage time.

[44] Two days later, it was announced that Hobbs would miss the rest of the season owing to the knee injury sustained during the match.

[45] Recovering from injury, Hobbs made his return to the team on 9 December 2012 in a 2–1 defeat away to Watford, pairing with Alex Bruce at centre-back.

[50] He signed a loan deal with Nottingham Forest on 16 July 2013, with a condition that it become permanent on a two-year contract at the end of the 2013–14 season.

[53] He scored his first goal on 28 September in a 1–0 home victory over Derby County, heading in an Andy Reid corner before half-time.

[55] However, on 31 January, Hobbs signed permanently for Nottingham Forest on a four-and-a-half-year contract, for a fee reported by Sky Sports to be worth "close to £1million".

[69] Hobbs signed a one-year contract with Championship club Bolton Wanderers on 30 July 2018 following a successful trial.

[74] Hobbs made three appearances for the England national under-19 team, playing in all of their matches as they failed to qualify for the 2007 UEFA European Under-19 Championship in the elite qualification stage.