[5] Ricketts began his career at Oxford United, making his first team debut on 8 October 2000 in a 2–1 Second Division defeat at rivals Swindon Town.

[17] The defender was part of the Hull team that won promotion to the Premier League for the first time in the club's history at the end of the 2007–08 season; he played in their Championship play-off final victory over Bristol City.

[19] Ricketts made 29 league appearances for the Tigers in their inaugural top-flight campaign, as they narrowly avoided relegation on the final day of the season.

[21] On 25 July 2009, fellow Premier League club Bolton Wanderers confirmed Ricketts had signed a three-year deal with them for an undisclosed fee.

In February 2011 he suffered a snapped Achilles tendon during an FA Cup replay against Wigan Athletic, which put him out of first team contention until the end of the year.

[24] Ricketts' contract expired at the end of the 2011–12 season but, despite Bolton being relegated from the Premier League, he signed a new two-year deal with the club in the summer of 2012.

[25] On 4 July 2013, after a season in which the team failed to make an instant return to the top flight, Bolton confirmed that his contract had been cancelled by mutual agreement.

[27] On the same day as his exit from Bolton, Ricketts joined Wolverhampton Wanderers of League One as a free agent in a two-year deal, reuniting with his former Swansea manager Kenny Jackett.

[32] Soon after he took on a coaching role at the club,[33] but on 21 March 2015, left to join League One promotion contenders Swindon Town on loan for the remainder of the season.

[43] After his retirement from playing, Ricketts integrated into coaching, inaugurally spending a week working alongside Brendan Rodgers's backroom staff at Scottish Premiership champions Celtic.

[44] A year into his role, Ricketts left to become the first team manager of National League club Wrexham, signing a three-year contract, beginning on 2 May 2018.

[46] During his brief spell in charge, Ricketts guided Wrexham to 13 victories out of a possible 23, with his side constantly being in the running to gain promotion to the Football League throughout his tenure.

[47] On 1 December 2018, he was told by club officials to stay away from their FA Cup second round match against Newport County, amid speculation that he was poised to be appointed the new manager of League One side Shrewsbury Town, a local rival.

[53] In the summer of 2019, Ricketts made more notable signings to strengthen the squad for the upcoming 2019–20 season, bringing in players such as Jason Cummings from Nottingham Forest, Sean Goss from Queens Park Rangers, Donald Love from Sunderland, Ethan Ebanks-Landell from Wolves and Aaron Pierre from Northampton Town.

[59] On 14 March 2020, Ricketts and his Shrewsbury side were scheduled to take on top-of-the-table Coventry City at St Andrew's, however the match was postponed due to the outbreak of COVID-19.

With first-team midfielder Josh Laurent leaving for Championship club Reading,[61] Ricketts looked to strengthen his Shrewsbury squad again in the summer of 2020.

[62] The club played their first pre-season friendly of the season on 11 August, beating Cymru Premier side Bala Town 3–0 at Telford United's New Bucks Head.

Two days later on 13 August, defender Omar Beckles rejected a new contract and subsequently also left the club, leaving a gap in Ricketts' defence.

On 2 September, Ricketts managed to fill the goalkeeper void, bringing in Montenegro international Matija Sarkic on loan from Wolverhampton Wanderers.