Background
Whatmough was born in Gosport, and played for Southampton.
Whatmough was born in Gosport, and played for Southampton.
Portsmouth
At the age of 13 he decided to leave Southampton F.C. He then went training with Portsmouth and joined their Academy still only aged 13. He signed a two-year scholarship deal with Pompey on 6 July 2012. On 14 August 2012, aged only 15, Whatmough appeared on the bench in a 0–3 away defeat against Plymouth Argyle.
He finished the season with 26 youth appearances, with the Academy being crowned champions.
On 19 August 2013, Whatmouth signed a three-year professional deal. On 28 September he appeared again on the bench, in a 2–4 away defeat against York City.
On 26 November, Whatmough made his professional debut, starting in a 1–2 home loss against Southend United. He signed a contract extension with Portsmouth on 10 April 2014, later revealing via Twitter that his deal was extended until 2017.
On 6 January 2016, Whatmough joined Havant and Waterlooville on a months loan to continue his rehabilitation from a serious knee injury which had kept him out since March 2015.
On 16 December, Whatmough was called up to train with England U18"son He then made his debut international debut on 5 March of the following year, starting in a 1–2 loss against Croatia at Street George"s Park.