[3] Upon his return to Motherwell, he made his debut against Aberdeen at Pittodrie at the age of eighteen[3] and thereafter became a regular in the side, making over 200 league appearances across seven campaigns.
[4] Hammell joined Southend United in July 2006 on a free transfer from Motherwell after his contract had expired – turning down more established sides such as Derby County, Southampton and Aberdeen.
Hammell came to speak to Southend manager Steve Tilson after a conversation with former Blues loanee Alan McCormack – also of Motherwell.
[8] Hammell rejoined Motherwell in the January 2008 transfer window on deadline day for a fee of £110,000, replacing Jim Paterson at left-back.
Earlier in the day Paterson had left the club to join Plymouth Argyle and the proceeds from this transfer were used to buy Hammell.
On 17 November 2004, Hammell made his full international debut for Scotland under caretaker manager Tommy Burns in a 4–1 friendly defeat to Sweden, coming on as a 54th-minute substitute for Hearts centre-back Andy Webster.
[21] In May 2013, after a nine-year absence from international duty, Hammell was drafted in to the Scotland squad for their FIFA World Cup qualifier against Croatia following injury doubts over other full backs.
[22] In July 2013, Hammell managed to retain his place in the Scotland squad to face England at Wembley in August.